THE ALZYLATIOIJ OF BaiJZSWfi. TOLUfillE Ai^D NAPHTHALENE
AIJD THE GHLOHIIJATION OF ACETYLENE
Submitted to the Board of University Studies of
The Johns Hopkins University in Conformity
with ii:equirements for the Legree of
Loctor of i-hilosophy
Thomas Llorris Berry
TABLE OF COlJTEiJTS
The Alkylation of Benzene, Toluene and ivaphthalene
The Present Investigation 2
Apparatus - Fig. I 3
The Ethylation of Benzene 4
Hatio of C5E5 to AIGI3 5
Examination of the Two Layers 7
Ethylation of Toluene 16
Ethylation of Brom Benzene 17
Propylene and Benzene 19
Propylene and Toluene 33
Propylene and Naphthalene 35
Tetrahydro Benzene and Benzene 35
The Chlorination of Acetylene
The author welcomes this opportunity to express his
deepest sense of gratitude to Doctor lieid, under whose
direction the first part of this work was done, and to
Doctors Prazer, Patrick, Lovelace and Thornton for the in-
spiration received in the lecture room and laboratories.
Appreciation is also extended to the authorities of
The Chemical .Varfare Service for permission to publish the
work on the chlorination of acetylene, which work was done
at idg-ewood Arsenal.
TH3 ALETLATION OF B3NZSIIE, TOLUENE AUD NAPHTHALENE.
Friedel and Crafts and later workers have shown that
benzene may he alkylated by treating it with an alky^ halide
in the presence of anhydrous aliuninum chloride -
RCl ^ C6H6 ^1^1_3> C6H5R -»- HCl
Balsohn-'- in preparing ethyl benzene modified the Friedel
and Crafts reaction slightly. Instead of using ethyl chloride,
he used ethylene and hydrochloric acid in proportions to give
ethyl chloride -
CgH^ -f- HCl > CgHgCl
Since ethyl chloride and benzene react in the presence of alum-
inum chloride to liberate hydrochloric acid, the total amount
of hydrochloric acid required in comparison with that of ethy-
lene is very small since it undergoes a cyclic process
C2H4 4- HCl > CgHgCl
HCl -H C6H5C2H5 ;
in fact Balsohn later found that even traces of water vapor
in the ethylene used were sufficient, on reacting with the
aluminum chloride, to furnish the required amount of hydro-
Balsohn's method consisted in bubbling ethylene through
1. Bull. SOG. Chim. (2) 31, 539 (1879).
a mixture of benzone and aluminum chloride at 70°- 90° C.
Under these conditions ethylation takes place very slowly;
consequently the practical importance of the reaction was
at that time not realized.
According to McDaniels-'- 1 volume of benzene at 80°C.
dissolves two volumes of ethylene. Since this solubility is
small it is important that the benzene be saturated continu-
ously with ethylene if the best results are desired. This
point was recognized by Milligan and Reid^ who used high speed
stirring to maintain a condition of saturation; as a result
they found that the obscure and apparently unimportant method
of Balsohn was, in reality, a very practical one - a reaction
which when performed with the aid of high speed stirring, far
outrivaled the usual method in which a previously prepared
alkyl chloride is employed.
TH3 PRESENT INVESTIGATION.
1. To study more thoroughly certain features of the
Friedel and Crafts reaction.
2. To apply the method of Balsohn in the alkylation of
Benzene, Naphthalene and Toluene, using high speed stirring.
3. To study the chlorination of acetylene, using
1. J. Phys. Chera. 15, 605
2. J. Am. Chem. Soc. 44. 206
The stirrer as is shovra in Figure I consists of a disc
two inches in diameter and three sixteenths of an inch thick
with holes three sixtyfourth of an inch in diameter bored
radially aroiind its periphery and terminating inside of a
small cone at the bottom of the disc. The disc is screwed
onto a tool-steel shaft which is connected by means of belts
and an intermediate pxilley to a 1700 R.P.M. motor. /Vith the
size of pulleys which were used speeds as high as 13,000 R.P.M.
could be obtained. The gas to be used was, after preliminary
drying and purification, introduced by an inlet tube ending
just Tinder the cone and thrown out through the small holes by
the centrifugal force of the rapidly rotating disc. A rather
closely fitting iron tube was placed around the stirrer shaft
and connected by suitable means to the frame of the stirrer.
This tube passed through the rubber stopper of the reaction
bottle and dipped below the surface of the liquid contained
therein; in this way a perfectly gas-tight reaction chamber
was obtained. Baffle plates were used to decrease the gyra-
tory motion of the liquid.
A condenser was attached at one end by means of an adapter
to the reaction bottle, while the other end was connected to
a receiver for unused gas.
THE STHYIATIOK OF BJCUZENS.
Tha ethylene used was of commercial variety but of a very
high grade of purity. It was first passed through a gas meter.
The difference between the amount of gas as represented by the
gas meter and the amount of recovered gas was taken as the
amount which had reacted. After passing through the gas meter,
the ethylene was purified and dryed. by passing through two
gas wash-bottles, one containing pyrogallic acid and the other
sxilphuric acid respectively; and then through two drying
towers filled with soda lime and another containg phosphoric
The gas was passed into the benzene-aluminum chloride
mixture at such a rate as to allow only an occasional bubble
to escape. This was found to be the method conducive to the
best resiilts, since if the amount of escaping gas is large, it
carries appreciably quantities of hydrochloric acid along with
it and the reaction slows down to a very marked degree. In
some cases it was possible to restore the original reactivity
by passing in small quantities of dry hydrochloric acid along
with the ethylene.
In all of the experiments, the temperature was held at
approximately 70°. It was found that the change of tempera-
ture coefficient of the reaction within the interval 60°-90°C.
is approximately zero.
Throughout the work it was found that an incubation
period of about twenty minutes before the passage of the
ethylene, favored the reaction.
Experience has shown that at any given Instant during
the course of a reaction, a maximum rate of absorption of gas
under the prevailing conditions can be obtained, only with
one particular rate of stirring. If the rate of stirring be
reduced below this point, a reduction in the rate of gas
supply must be made; while on the other hand, if the rate of
stirring is increased, a corresponding escape of gas takes
place with the consequent loss of hydrochloric acid, and, as
a resiilt the reaction slows down to a very marked degree.
The rates of stirring ranged between 8,000 and 10,000 E.P.LI.
RATIO OF C5H5 TO AICI3
It was desirable to know the relative proportions of
benzene and aliuninum chloride which would afford a maximum
rate of reaction. It is quite conceivable that if this ratio
be either very large or very small a poor rate of reactions
will be obtained. The Inclination is to use a large amount
of catalyst with the hope of insuring a good rate of reaction;
it has however been fo\md that an excess of aluminum chloride
is Just as detrimental to the rate of reaction as an insuf-
ficiency. The aluminiun chloride used in all of the experi-
ments in one set was from the same lot.
Slnoe the usual course of a catalytic reaction is to in-
crease up to a maximum and then decrease, a comparison of
results can be obtained only by counting time from the in-
stant at which the introduction of the ethylene is begun,
since the rate of increase of reaction rate varies in the
different experiments. In table I the rates of absorption
for a period of 134 minutes after the introduction of the
ethylene are listed for five different experiments in which
varying relative amounts of aluminum chloride and benzene
Average Hate of
cc. CgH^/Mol CgHg/LIin
It thus appears that better results are obtained when the
ratio of aluminum chloride to benzene lies between 1 : 13 and
1 : 22 . Ratios greater than 1 : 13 give poorer results while
a ratio as small as 1 : 44 gives practically no results.
EXMIIMTION OP THIi TWO LAYERS
Friedel and Crafts^, Gustavson, Boeaeken and others have
fotmd that in the Friedel and Crafts reaction, there are always
two layers formed. A clear upper layer and a dark "brown, very
viscous lower layer. They state that the upper layer contains
mostly benzene and the low boiling products, i.e. the lower
substituted benzenes, while the lower layer contains materials
boiling at much higher temperatures. An explanation for this
phenomenon makes its appearance on consideration of the various
theories which have been proposed to explain the mechanism of
the Friedel and Crafts reaction. Friedel and Crafts own theory
was, that the aluminum chloride used combines with the benzene
to form a compound CgH5.Al2Cl5 which later reacts with the alkyl
chloride giving hydrochloric acid and a substituted benzene
CgHgAlgClg + RCl -> CgHgR -V HCl
This theory was later abandoned for the theory proposed by
Gustavson*^ who attributed the condensation to the formation
of addition products of aluminum chloride with three molecules
of benzene AICI3.3 CgHg; products which have been isolated and
analyzed. These addition products are attacked very easily by
1. Ann. Chim. Phys. 6, (1), 449
2. B. 12, 853; 13, 157; 16, 784; 33, 767.
AICI3.3 C5H5 + 3 RCl -> 3 HCl -V AlClg.SCCgHsR)
AICI3 -+ 3 CgHgE
Boeseken-^ has shown that Gustavson's intermediate is
formed only in the presence of traces of moisture. He also
shows that Gustavson's assiimption, that one mol of AICI3 suf-
fices for 3 mols of hydrocarbon and three mols of alkyl
chloride, is not valid in certain cases, since in these one
mol of AICI3 will condense only one mol of hydrocarhon and
one mol of alkyl chloride. He contends that the aluminum chlo-
ride confines with the alkyl halide and has isolated some of
C5H5COCI.AICI3 -t- C5H5 -^ C5H5COC5H5.AICI3
Boeseken^ points out that in the formation of homologues
of "benzene, a very small amount of AICI3 was sufficient to
cause the reaction of a large amount of alkyl halide. This,
he explained, was due to the inability of AICI3 to form very
stable compounds with the reactants.
All of the theories which have been proposed assume that
!• Boeseken - A. ch. (G) 14, 467
E. Boeseken - Rec. Trav. 22, 301
aluninum chloride forms an addition product with the alky-
lated benzene. If this be true, then we should expect to
find at the end of our reaction, the most alkylated benzenes
in corabination with the aluminum chloride.
This point was investigated by first separating the two
layers, as well as possible, by siphoning off the upper layer.
The two layers were then treated separately with water to de-
compose the aluininiim chloride complexes. The amounts of these
complexes, in the upper layer, are very small as is shown by
treating with water; practically no heat is evolved and only
very small amounts of aluminum hydroxide precipitate. The
lov/er layer, on the other hand, contains practically the whole
of the aluminum chloride used and has to be decomposed extremely
slowly and with constant cooling. The upper and lower layers
were fractionated separately through a Vigreux column. It
was found that the lower layer contained, by far, a higher per-
centage of the more alkylated benzenes.
The following ratios will indicate the relative molecu-
lar amounts of the different ethyl benzenes appearing in the
upper and lower layers. These calculations were made upon
the basis of 1000 molecular weights of mono ethyl benzene
appearing in the upper and lower layers respectively.
Prom the data given, it is quite apparent that there is
a marked difference in the composition of the two layers. In
run #£ the reaction was stopped in its early stage, i.e. after
considerable quantities of mono- and di-ethyl benzenes had
been formed. Run #12 was carried much further toward completion
and as a restilt higher percentages of the more ethylated
benzenes were obtained. In all of the runs which v/ere made, it
was observed that an extraordinary high percentage of penta
ethyl benzene was obtained in the lower layer as compared with
that in the upper layer.
In all of the experiments it was observed that the speed
of the reaction increased up to a maximum, remained constant,
and then began to decrease. Experiment #13 shows this rather
clearly. In the following table the rates are given in cc. of
ethylene absorbed with their respective periods of absorption.
. of C2H4
Fig. 2 is a graphic representation of these values.
The manner in which the benzene was dryed had considerable
influence on the reaction. Calcium chloride-dryed benzene on
being stirred with aluminum chloride gave rise to hydrochloric
acid fumes which hovered above the surface 6f the benzene.
After the reaction had progressed for some time these fumes
gradually disappeared. Reactions in which calcivin chloride
dryed benzene was used appeared to be very sensitive to changes
in temperature, rate of stirring and loss of hydrochloric
acid, and further, maintained the maximum rate for only a
\ 1-i--:| i
Time In h^l i nutes
20 40 60 80 100 120 (40 ISO 180 ^oo zio z^q
short period as compared to sodium-dryed benzene, which did
not yield white fumes of hydrochloric acid on being stirred
with alwnintun chloride.
iixperiment #E gives a fair idea of the rate at which
benzene can be ethylated. 5.83 mols of benzene were ethy-
lated with 139 Z. of ethylene, in the presence of 60 g. of
AlCl-3 over a period of 134 minutes. The average rate of
ethylatinn being 1034 cc. of ethylene per minute. The above
amount of ethylene was calculated from the products obtained
which were -
123 g. Benzene
200 g. iithyl benzene
155 g. Di ethyl benzene
42 g. Tri ethyl benzene
18 g. Tetra ethyl benzene
13.5 g. Penta ethyl benzene
16 g. Hexa ethyl benzene
It has been previously stated that the reactions were run
so as to permit only an occasional bubble of ethylene to escape.
In this experiment calculation shows that 97 % of the ethylene
sent into the reaction bottle is present in the distilled
products. In this experiment 3.85 mols. of benzene, 0.385 mols
of AICI3 and 14.1 mols of ethylene were made to react over a
period of 675 minutes. The products obtained were -
l/2 g. Benzene
4 g. Ethyl benzene
74i- g. Di ethyl benzene
305 g. Tri ethyl benzene
8E g. Tetra ethyl benzene
31 g. Penta ethyl benzene
154 g. Hexa ethyl benzene.
It was not possible to ethylate the benzene directly to
hexaethyl benzene with the apparatus which was used in this
work, due to the increase in volume of the liquid mixture
on ethylati6n. The volume change is about 100 °io for an
ethylation of about 80 per cent.
Experiment # 13 is interesting from the standpoint of
the comparative ease of ethylation of benzene and diethyl
benzene. A mixture of 2.E4 mols of diethyl benzene and 0,385
mols of aluminum chloride was ethylated at a rate of 900 cc.
per minute for 233 minutes. In this experiment benzene and
aluminum chloride were employed in the ratio of 1 : 5.7 and
the average rate at which the ethylene reacted for a period
of the first 134 minutes amounted to 257 cc. per mol of di-
ethyl benzene per minute. This is a much higher rate than
would have been obtained had benzene and aluminum chloride
been used in the above proportions. If diethyl benzene
ethylates at the same rate as benzene we would have expected
a lower rate of absorption. It appeared throughout this
work that alkylated benzenes alkylate with somewhat greater
ease than does benzene; in other words it is harder to sub-
stitute the first alkyl group into the benzene ring than it
is to substitute the second alkyl group. This experiment
was stopped on account of the product solidifying in the re-
action bottle and consequently preventing further stirring.
There were obtained on separation -
447 g. Hexa ethyl benzene
32 g. Tetra ethyl benzene
4 g. Penta ethyl benzene
3 g. Residue
The amount of ethylene which reacted in this experiment
represents 822- % of the amount required to convert all of
the diethyl benzene into hexa ethyl benzene. Of the amount
of ethylene which reacted 86-2 % was accounted for in the
hexa ethyl benzene obtained after centrifuging out the in-
In experiment #14, 2.24 mols of tri-ethyl benzene were
ethylated with 5.03 mols of ethylene; 6.385 mols of AlClg
were used and the reaction run for a period of 248 mimites.
The average rate was 240 cc. per minute for the first 134
minutes as compared with 257 cc. per mol of diethyl benzene
as was stated in the previous experiment. From these results
it appears that tri-ethyl benzene can be alkylated at ap-
proximately the same rate as diethyl benzene but both of
these at a greater rate than benzene. This reaction was
stopped before the products in the reaction bottle solidi-
fied. On separation there were obtained -
345 g. Hexa ethyl benzene
10 g. Penta etliyl benzene
70 g. Tetra ethyl benzene
22 g. Tri ethyl benzene
The amount of ethylene which reacted corresponded to 72-^ %
of the amount required to carry all of the tri-ethyl benzene
to hexa-ethyl benzene; of this amount 8C.1 percent went to
form hexa-ethyl benzene.
It was expected that by stirring gaseous ethyl chloride
into a mixture of benzene and alumintim chloride that the
ethylation would take place somev^at faster, since a certain
amount of time must be consumed in its formation from ethy-
lene and hydrochloric acdi. Commercial ethyl chloride after
drying was passed into a mixture of benzene and aluminum
chloride. In this reaction one mol of hydrochloric acid is
liberated from each mol of ethyl chloride which reacts; con-
sequently the escaping hydrochloric acid carried large amounts
of ethyl chloride along with it and as a result a large loss
was involved. On the whole, this method was very unsatis-
factory as compared with that in which ethylene was used.
The reaction between ethylene and benzene in the presence
of AICI3 is exothermic and a cooling coil was placed aroimfl.
the reaction bottle vixich was immersed in a water bath; this
was used in case the mixture got above 70^0.
It was fotmd that the reaction was aided "by allowing
the temperature to rise, at the "beginning, tmtil gentle re-
fliLicing was taking place. The refluxing was allowed to con-
tinue for several minutes, after which the mixture was cooled
to 700C. Refluxing for short periods of time tended also
to revive the reaction after it had slowed down.
Two different boiling points are given in Beilstein for
Hexa-ethyl Benzene namely 305°C. and 292°C. In this work
a total of about 1400 grams of hexa- ethyl benzene were pre-
pared; consequently, it seemed that advantage should be taken
of this opportunity to obtain its boiling point. After 3
recrystallizations from hot alcohol, the boiling point as
determined with a 400 g. sample was found to be 293°C. at 766
ETHYLATIOII OF TOLUNSKS.
3.04 mols of toluene were treated with ethylene at a rate
of 811 cc. per minute for a period of 81 minutes. This re-
presents a rate of 266 cc. per mol of toluene per minute.
This is a greater rate of ethylation than could be obtained
with benzene. On fractionation of the product under ordinary
pressure the following fractions were obtained:
Up to 120° C.
120 - 145°
145 - 160°
160 - 164°
164 - 171°
- mostly toluene
- a mixture of dimethyl and ethyl
- ortho- and meta-mGthyl ethyl
- p. ethyl methyl benzene
1.3,5 trimethyl benzene and
1.2.4 trimethyl benzene
171 - 198° = 28 g. 1.2.3 trimethyl benzene and
220.127.116.11 and 18.104.22.168 metaethyl dimethyl benzene
198 - 203° 2 32 g. 3.5 diethyl -1-ipethyl benzene. This
fraction had an intensive blue fluorescence.
203 - 207 = 33 g. 22.214.171.124 tetra methyl benzene
5 g. Residue.
The ethyl-methyl benzenes have been prepared by the
ETHYLATION 0? BROM BSIIZSITS
2.83 mols of Brom Benzene were ethylated at a rate of
70 cc. per mol of brombenzene per minute for a period of
345 minutes using 0.375 mols of aluminum chloride. Toli^ene,
on the other hand , was etlaylated at a rate of 266 cc. per
minute per mol of toluene under nearly the same conditions.
1. Glaus - B. 18, 1121
vVroblewski - A. 192, 198
?ittig & Gliazer - A. 136, 312
Jannasch & Deickmann - B. 2. 1513
It appears that alkyl side chains Increase the rate at
which the "benzene ring can be alkylated, while halogen
substituents effect a retardation. Previous workers have
shown, that AICI3 causes a shifting of halogen atoms in the
benzene ring. This, as would be expected, took place in the
ethylation of brombenzene. On fractionation of the product
we obtained the following fractions:
Up to 140° C. - 15 g. - a mixture of benzene and ethyl-
140 - 180" r 135 g. Sthyl- & DlEthyl-Eenzene
180 - 204° z 47 g. - 2 brom-1-ethyl benzene
204 - £15° = 39 g. - 4 brom-1-ethyl benzene
215 -221' z 45 g. - Triethyl benzene and dibrom benzene
221 - 240° - 35 g. Brom-diethyl benzenes.
240 - 250" r 35 g. Decomposed with liberation of
Residue = 85 g. - Tar
PROPYIENE AND BSRZERS
Gustavson-^ has shown, that when normal propyl bromide
and isopropyl "bromide react with "benzene in the presence
of alumintan chloride the same compound, namely isopropyl
"benzene, is o"btained. It is evident from this that the
alximinum chloride causes a transformation of the one form
of propyl "bromide into the other.
Kekule and SchrOtter have shown that normal propyl
"bromide under the influence of AICI3 splits off HBr and re-
arrangement is brought about giving isopropyl bromide:
H H H H Br H
H-C-C-C-Br J^±ll^ H-C-C-C-H
H H H H H H
This action is a minimum at 0°C.
From 60 g. of propyl bromide and 80 g. of Benzene,
Gustavson obtained 20 g. of isopropyl benzene, a yield of 34%.
Jacobsen^ prepared isopropyl benzene by the ?ittig
method using 100 g. of isopropyl iodide and an excess of
benzene. After a reaction period of 4 days he obtained 5 g.
of isopropyl benzene, a yield of 7%.
1. B. n, 1251
2. Bl. (4) 3, 726
3. B. 8. 126U
Liebman-^ prepared isopropyl benzene from benzal
chloride and zinc methyl
LI CU3 , . /CH,
"^ CI CH3 ^ ^ ^^^3
Since isopropyl benzene can be prepared only very slowly
by the above methods, which furthermore afford very low yields,
it was hoped that the reaction between propylene and benzene
in the presence of AICI3 would prove a better means for its
Propylene was generated from isopropyl alcohol by drop-
pinsr it upon raeta phosphoric acid at a temperature of 500°-
700° C. This method, although it yields propylene of a very
high degree of purity, is undesirable from the standpoint of
the destructive action of phosphoric acid upon the glass
reaction vessel at this temperatiire. The action was such
as to gradually eat away the bottom of a pyrex flask in the
course of ten hours under running conditions.
A slightly less pure grade of propylene (less reactive)
can be obtained more readily, and in larger amounts, by pass-
ing isopropyl alcohol vapor over pumice impregnated with
■^^2^3 ^^^ ^Q^^ ^"t a temperature of about 600°C. The pumice
1. Liebman - B. 13. 46
so impregnated may be naed for a period of 6 - 8 months
before yielding an undesirable grade of propylene. The
propylene was collected in a tank over water and after
passage through a gas-meter was purified as in the case of
The rate of reaction between propylene and the benzene-
altuninum chloride mixture was much slower than when ethylena
was used. This might be explained as being due to the in-
crease in weight of the isopropyl radical over that of the
In experiment #18, 15 mols of benzene were treated with
propylene at a rate of 122 cc. per minute or 8 cc. per minute
per mol of benzene for a period of 1770 minutes in the presencf
of 1.1 mols of AICI3. This is a rate of about l/25 that at
wliich it was possible to ethylate benzene. The two layers
on fractionation gave the following products:
up to 75°(b.p. 28°)
54 g. Benzene
Mono Isopropyl Benzene
82 g. 135 - 155°
Di Isopropyl Benzene
32 g. 200 - 22C°
28i g. 220- 255°
16 g. 225 - 285°
75 g. Residue
The molal relationship of these products existing in the two
layers, calculated upon the "basis of 1000 mols of inono-
isopropyl benzene existing in each layer, is -
Mono Di Tri Tetra
Top 1000 : 497 : 66 : 13
Bottom 1000 : ^85 : EOO : 100
From this relationship it is apparent, as was the case
with the ethyl benzenes that the bottom layer is relatively
richer in the more highly substituted benzenes than is the
upper layer. The crude product in this experiment differs
from that obtained in the ethylation of benzene in that a
fraction boiling below 75° was obtained and that further,
the bottom layer always contained a high percentage of tar.
The isopropyl benzenes which appear in the literature at the
present time are - mono-, ortho- and meta-di and 1:3:5 tri-
isopropyl benzene. By a study of the temperature intervals
existing between the boiling points of the ethyl benzenes a
very good idea was obtained as to the temperature limits
between which the higher substituted isopropyl benzene fractions
should be taken; after the boiling points of several of these
higher products had been obtained it was apparent that the
fractions had been cut within the proper ranges.
In experiment #21, 14 mols of benzene were treated with
100 cc. of propylene per minute (7 cc. per min. per mol of
benzene) for a period of 2551 minutes in the presence of 1.1
mols of illClg. The crude prodilcts yielded -
22 g. up to 75
252 g. Benzene
720 g. Liono Isopropyl Bnezene
293 g. Di
29 g. Tri
16 g. rlesidue
1000 : 299
1000 : 180
It was noted throughout this v/ork that the complexes
of AlClg with the isopropyl benzenes were decomposed more
slowly "by water than were the complexes "between AICI3 and
the ethyl "benzenes.
It "became the additional o"bject of this work at this
point to prepare some of the higher isopropyl benzenes. It
is apparent from the data so far presented that mono- and
di- isopropyl benzene may be prepared in large amoxmts by the
reaction between benzene and propylene. After several attempts
to carry the reaction to such a stage that the products
would consist largely of the higher alkylated benzenes it
was found that time was saved by first isolating the lower
products and then retreating these with propylene in the
presence of AlClr^. It was also interestiriR: to find out
whether or not the isopropyl benzenes and propylene react
with greater ease than benzene and propylene.
In experiment #23, 3 mols of mono isopropyl benzene wer(
treated with 42 cc. of propylene per minute (14 cc. per mol
of mono isopropyl benzene per minute) for a period of 1655
minutes. Prom these results it is again apparent that an
alkyl benzene may be alkylated with greater ease than benzene
The two layers on fractionation yielded the following:
up to 75°
I.iono Isopropyl Benzene
Di " "
Tetra " "
The percentage of each product occurring in each layer
In this experiment a total of 452^- grams of the tri iso-
propyl benzene was prepared. This product contains about
92% of the propylene used in the experiment.
In experiment #22, 10.6 mols of mono- iijopropyl benzene
were treated with propylene at a rate of 16 cc. per mol of
propylene per minute (total of 170 cc. per minute) for a
period of 1388 minutes in the presence of 60 g. of AICI3.
The total products from the two layers were fractionated and
refractionated several times to gain an idea of the relative
isomeric yields. The fractions obtained were:
17 g. up to 75° at 766 mm.
20 g. Benzene 75 - 90 °
i g. 90 - 152
220 g. Llono 152 - 156 (B.P. 152 - 154)
25 g. Mono- Di- 156 - 201
33 g. Mono- Di 201 - 203j
203 J - 204i (B.P. 204)
2044- - 205-1-
206 - 206V
206;^.: - 208^
208^- - 209V (B.P. 209)
212 - 215
215 - 220
220 - 225
225 - 230
230 - 233
256 g. 1.3.5 Tri 233^-234'; (B.P. 234)
56 g. 2341 - 235V
46 g. 236V - 236^
236^ - 237^
238 - 239
239 - 24C
240 - 241
242 - 243
243 - 246
It appears from this data that about 65/o of the di-
isopropyl benzenes formed is the meta. Of the tri-isopropyl
benzenes fromed, about lb% is symmetrical tri-isopropyl
250 g. of 1.3.5 tri-isopropyl benzene was treated with
56 1. of propylene in the course of 12 hours. This reaction
went at an exceptionally high rate; it being possible to
cause an absorption of 80 cc. of propylene per minute. The
reaction was not allowed to go to completion. On cooling
the products in the reaction bottle solidified. On purifi-
cation it was found that a white solid had been formed which
was identical with the 2 grams of white crystalline compound
obtained in experiment #23. The fractions obtained from the
crude material were:
5 g. 234 - 236
48 g. 236 - 245
14 g. 245 - 260
24 g. 260 - 265
15 g. 265 - 270
110 g. above 270
26 g. 'iVhite crystals.
Several runs were made using tri-isopropyl benzene and
it was found to be possible to run the reaction until the
products solidified completely. A total of 65 grams of the
white crystalline material was prepared. It was centrifuged
free of included oils and recrystallized several times from
alcohol. The material crystallized in the form of long white
needles which had a melting point of 117° and a boiling point
of 260° at 775 ram. This material was oxidized with a 7/'b
soli^tion Oi' permanganate on a water bath for one month and an
acid melting at 282° was obtained. This could have been either
mellitic acid of m.p. 286° or the dianhydride of 126.96.36.199 tetra
carboxylic acid of melting point 286° C; hov/ever it would not
be expected that the anhydride of this acid would be formed
under the given conditions.
The silver salt of this acid was prepared and gave an
analysis 65.42 % Ag, the theoretical for s41ver mellitate
being 65.82 °lo^ while the theoretical for the silver salt of
benzene tetra carboxylic acid is 63.32 /b. The boiling point
of the hydrocarbon (260° at 775 mm.) indicates that it Is
tetra isopropyl benzene rather than hexa isopropyl benzene
since its boiling point lies far belov/ that of hexa etiiyl
benzene (294°); also oils boiling above this were obtained
(E65^° and 270°C.) which are thought to be tetra isopropyl
benzenes. Mirtirros of oils boiling even higher than 270°
were obtained but in insufficient quantities for separation.
The 188.8.131.52 tetra methyl benzene boils below its two isomers,
it being a solid while the isomers are liquids at room tem-
perature. The boiling points of the hexa alkyl benzenes in-
crease with increasing complexity of the alkyl groups as
would be expected, hexamethyl benzene boiling at 254 ° and
hexaethyl benzene at 294°; therefore we should expect hexa-
isopropyl benzene to boil higher than 294°C. A combustion
was made on this hydrocarbon and the following analysis
Hexa Penta Tetra
% C 87.43 87.18 87.41 87.72
fo H 12.43 12.82 12.59 12.28
Since p. diisopropyl had not been made, considerable
time v/as spent in trying to locate it within the range of
the boiling points of the meta and ortho diisopropyl benzenes.
The attempt to isolate this material failed, however, althoiigh
it is thought that it boils between 212° and 216° since such
a fraction was obtained which was quite resistant to further
separation. Hot enough of this fraction was obtained, how-
ever, to effect an adequate separation.
An attempt was made to synthesize para diisopropyl
benzene by means of the Fittig synthesis. 240 grams of iso-
propyl benzene were brominated with 321 grams of bromine in
the presence of 30 g. of iodine at 0°C. On fractionation
of the product there were obtained 290 g. of para brom-
isopropyl benzene and 40 grams of oriho brom isopropyl benzene.
Isopropyl chloride was obtained by refluxing isopropyl
alcohol with an excess of concentrated hydrochloric acid,
using a Hempel coltunn mounted by a 40" Vigreux column. By
using this arrangement and carrying on the distillation so
that the material does not distill above 50° a fairly rapid
preparation of isopropyl chloride may be obtained. The para
brom-benzene was mixed with its molecular equivalent of iso-
propyl chloride and the mixture treated with the calculated
quantity of sodium. The product on being separated yielded
75 g. of a fraction 150°-1570c.
300 g. of an earthy material.
The fraction 15C°-157° was oxidized with permanganate, and
benzoic acid of melting point 121°-122° obtained. It is
evident from this that the bromine of para brom-isopropyl
benzene was replaced by a hydrogen atom. This evidently
came about as a result of the splitting off of hydrochloric
aoid from isopropyl chloride which thon reacted with the
para brom benzene through the agency of the sodium to give
isopropyl benzene. It was noticed while the reaction was
tailing place that a gas was being liberated, this gas was
The earthy material was very light in v/eight, had a
dark brown color and was insoluble in all of the common
organic solvents; even on extraction with xylene for several
days using a Soxlett apparatus nothing dissolved. The
material burned in a manner much like cork and emitted a
grayish smoke having a peculiar odor. This material is
likely a polyphenyl compound.
Jacobsen-'- states that it is very hard to put even one
isopropyl group into the benzene ring by the Pittig Synthesis
since the isopropyl halide is attacked with difficulty by
sodium. After allowing brombenzene and isopropyl iodide to
react for four days in the presence of sodium he obtained
only a 5^i yield. Sprinkmeyer^ tried to prepare ortho iso-
cymol ^yyj . y, from ortho brom toluol, isopropyl iodide
f 1 ■"
and I I sodium but failed to get any of the de-
I J sodii
sired product; he was however able to prepare small amoxmts
of it from ortho bromcumol /■\_-\3,r • ^^'ti^yl iodide and
1.3.5 Triisopropyl benzene has been prepared 3. YhQ
1. Jacobsen - Ber. 8, 1260
2. iprinkmeyer - Ber. 34, 195
3. Comi^t. rend. 140, 940 ; C 1905 (11) 379;
J. prak. Chem. 2 72.. 57
1.2.4 isomer was obtained as a result of the present work
by refractionating the triisopropyl benzene fraction a number
of times in a vacuiim using a pressure regulator. A total
of 300 grains of this oil was obtained having a boiling point
of 237°-237i° at 752.5 mm. and 97°- 97';-° under 4 mrn. It was
oxidized for five days on a v/ater bath by a 7 percent solu-
tion of permanganate. An acid melting with anhydride for-
mation at 214° was obtained, this evidently is 1.2.4 benzene
tri-carboxylic acid. The oil Ijad a specific gravity of
0.87644 at 0°C. and of 0.85928 at 250c. It had a color of
+ 18 as determined by the method recommended by the ^Imerican
Society for Testing Ilaterials using a viscosity of 21.7
seconds at 100°?. for 30 cc. using a Sabolt Universal Vis-
cosimeter; 30 cc. of v/ater under the same conditions gave a
viscosity of 17.4 seconds. The index of refraction was found
to be 1.4855 at 25°C. The oil gave a flash point of 205°:\
and a fire test of 245°i\
200 grams of another oil were isolated. This had a
boiling point of 270°C. at 766 mm. It had a color of -12
and flash and fire points of 240° and 280°?. respectively.
The specific gravity was found to be 0.91283 at 0°C. and
0.89658 at 25°C. Its refractive index at 25°C. was found
to be 1.5060. Its viscosity as determined with 30 cc. of
oil was 45.7 seconds at 100°?.; the same amount of water at
this temperature required 17.4 seconds. This oil was oxidized
with permanganate and an acid having a melting point of
About 60 grams of another oil was isolated. It had a
boiling point of 265V°C. at 755.7 mr.i. and 10Zlr°C. at 4 mm.
and refractive index 1.49G9. Color -7.
The fraction boiling belov/ 75° was refractionated and
fomid to be composed of two substances one boiling at 28°C.
and t]ie other from 56°- 59°. The latter is likely diiso-
propyl which has a boiling point of 58°C. The former had a
specific gravity of 0.70949 at 0°G.
2.5 dibrom isopropyl benzene was prepared by brominating
120 grams of isopropyl benzene with 325 grams of bromine in
the presence of iodine at a lov; temperature. 235 grams of
a liquid boiling at 258°- 259° and having a refractive index
of 1.5718 at 25° was obtained. This oil was oxidized with
permanganate and an acid having a melting point of 151°C.
was obtained; this is evidently 2.5 dibrom benzoic acid which
melts at 151°-155°.
PROPYLSNil AlID TOLUSKi:
Kel"be states that by treating toluene v/ith isopropyl
iodide in the presence of alvj-ninun chloride meta i30c;>-mol
is obtained. Flttig attempted to prepare para methyl iso-
propyl benzene from para broratoluol, isopropyl iodide and
sodiiun but failed to get the desired product^. However,
Widman^ prepared it by the Pittig sjmthesis using para-
brom-isopropyl benzene and methyl iodide.
7.2 mols of Toluene were made to react with 2-5- mols of
propylene at a rate of 75 cc. per minute in the presence of
ICO g. of AlClg. It is to be noted that this reaction goes
somewhat faster than that between propylene and benzene.
The product after purification was fractionated into the
foil owing :-
5 g. Benzene
370 g. Toluene 1050-1200
17 g. Xylene I20O-145O
25 g. 145°-170° A mixture of trimethyl benzene
and ortho c:,Tnene
161 g. 170°-185° of meta isocyraene (175-176) and
cymene (para methyl isopropyl ben-
60 g. above 185°
If the fraction 170°- 185° be a mixture of meta-and para-
1. Ann. 210, 10
2. iUin. 149, 337
3. Ber. 24. 450
methyl isopropyl benzenes , a possible separation could not
be obtained merely by distillation, since both boil at the
same temperature. The mon- brom derivatives of these com-
pounds hov/ever, boil at about ten degrees apart; that of
the meta compound at about 224° and those of the para at
136^^- grams of the fraction 175-176, obtained by redis-
tillation of the original 17C°-185° fraction, was brominated
in the cold, using 10 g. of iodine as a carrier, with 162
grams of bromine. The product after being washed and dryed
gave the follov/ing:
3.7 g. - 160°-195° C.
11.2 g. - 195^-220° 0.
para 160 g. - 228°- 240°G
6 g. - 2400-2470C.
£5 g. - Residue
The fraction 228°-240°C. represents a yield of SO^-i of the
brom derivatives of para- methyl isopropyl benzene, llelbe-'-
states that by the Friedel and Crafts reaction using toluene
isopropyl iodide and AlClg he obtained meta methyl isopropyl
benzene. He obtained only a small quantity of his product
and his method of identification which consisted in observing
the solubility of barium salt of the corresponding di-carbox-
ylic acid was unsatisfactory.
1. Ann. 210 . 10
PROPYLENE AIID NAPTHAIEIIE
Since ethylene and napthalene react only very slowly
in the presence of iUCl^, it was to be expected that pro-
pylene and napthalene would react even slower. Instead of
propylene, diisopropyl benzene was used.
217 grams of napthalene was stirred with 132 g. of di-
isopropyl benzene in the presence of 50 g. of AICI3 at a
temperature of 90°C. for a period of 4-^- hours. The product
on fractionation gave the following:
72 g. mono isopropyl benzene 15C°-185°
72 g. of napthalene 185°- 250°
15 g. isopropyl napthalene (264°-2660)
9 g. E66°-50C° probably diisopropyl napthalene.
50 g. of an oil boiling above 300° C.
T3TRAHYDR0 BENZSHS AIJD BENZEIIE
Since tetrahydro benzene contains an ethylene lini:age
it was thought that it would react with benzene in the same
manner as has been shov/n in the case of ethylene and pro-
pylene. The product expected was phenyl cyclohexane
:0: tc. - ^"v-;
3.54 mols of totra-hydro benzene were mixed with 3.54
mols of benzene and treated very gradually with 60 grama
of AICI3. On the addition of the AICI3 a violent reaction
tool: place with the liberation of large amounts of heat.
After the 60 grams of AICI3 had been added, the reaction
bottle was connected with the stirrer. The mixture could
not however be stirred for periods longer than 30 seconds,
as the amount of heat liberated was sx;ch as to cause the
liquid to boil. As the reaction proceeded the mixture could
be stirred for increasing periods of time. After about 45
minutes it was possible to stir the mixture continuously and
this was done for a period of five hours; during which the
temperature of the mixture remained at about 55 degrees.
At the end of five hours of stirring the temperature began
to fall. The reaction product was purified and dryed and
on distillation gave the following fractions:
30 g. up to 230° - mostly benzene, cyclohexyl chloride
(141.3) and tetrahydro benzene
50 g. 2300-245° Phenyl cyclohexane
125 g. above 245° - lil:ely diphenyl cyclohexane and
small amounts of dihexyl .
Ilursanoff-^ prepared phenyl cyclohexane from cyclo-
hexyl chloride, benzene and AICI3.
1. Ann. 518. 310
To 100 grams of benzene and 10 grams of AlCl^ ho
added slowly 50 grams of AICI3 he added slowly 50 grams of
cyclohexyl c}iloride and obtained the following prodiicts:
10 g. up to 130° mostly benzene
34 g. 1300-1320 (10 mm.) Phenyl cyclohexane
1 drop 1320-200° (10 mm. )
16 g. 2000-515° (20 mm.) diphenyl cyclohexane
Ke showed that the latter was an ortho compound by prepar-
ing it from ortho dichlorcyclohexane.
Kursanoff states that the more AICI3 used the lower the
percentage of phenyl cyclohexane obtained while the higher
the percentage of higher boiling products. As an example of
this he obtained a 11 percent yield 01 phenyl cyclohexane
by using 30 g, of AlCl^, 20 g. of chlor cyclohexane and 40 g,
of benzene whereas by using 0.1 g. of AICI3 under the same
conditions he obtained a 68 percent yield of phenyl cyclo-
hexane. This night explain why in the present work such
a high percentage of higher boiling prodiicts were obtained.
An effort was made to prepare phenyl cyclohexane by
the Pittig synthesis. To 15 grans of finely divided sodium
65 cc. of alcohol free dry ether were added. A nixture
of 35 g. of brom benzene and 35 g. of cyclohexyl bromide
were then added. The reaction began immediately and cooling
was necessary for its control. After standing over ni.'^ht
the product was distilled. A yield of 6-7 grans of phenyl
cyclohexane was obtained which corresponds to about 18',>; -
20-/i of the theory.
Phenyl cyclohexane has also been prepared by reducing
diphenyl v/ith hydrogen in the presence of catalytic nickel"'-.
1. Benzene, Toluene and Ilapthalene may be alkylated
readily by define and Polymethylene hydrocarbons in the
presence of aliuniniim chloride with the aid of high speed
stirring. By this method these alkyl compounds may be
prepared more rapidly than is possible by the ordinary
Priedel and Crafts reaction.
2. The rate at which alkylation will take place de-
pends largely upon the relative amcants of aromatic hydro-
carbon and aluminum chloride used.
3. The two layers which are always obtained in the
?riedel and Crafts reaction differ widely in the percentage
of products present. The AlCl^ which is found almost wholly
in the lower layer retains the higher boiling or more al-
4. The lower alkyl benzenes may be alkylated with
1. 0(1912) 11, 191
greater ease than benzene.
5. The larger the alkyl group the more difficult ii
its entrance into the benzene ring.
THii CHLOI^INATIOIJ OF ACETYLENE
The object of this work was to prepare tetra- and
hexa-chloretharles from chlorine and acetylene using a
liquid medium into which the two gases could be dispersed
by means of a high speed stirrer, it was thought that
saturation with water vapor, of the gases included within
the Eiinute bubbles occasioned by the vigorous stirring,
might cause a change in the usual course of the reaction.
The reaction usually proceeds with explosive violence to
give hydrochloric acid and free carbon.
Chlorine and acetylene were introduced into the cone
of the stirrer simultaneously by different inlet tubes.
500 cc. of water was placed in the reaction bottle
and a run made at room temperature. Explosions took place
continuously from the start which gave rise to numerous
scintillations throughout the liquid. It was thought that
by using a large excess of one of the gases that the ex-
plosions could be prevented, but this was found not to be
true. Explosions took place in every case irrespective of
the richness of the mixture. It was then decided to pass
the gases into boiling water v/ith the view that the increase
in water vapor would tend to dilute the P:a3es and thereby
reduce the violent action, iixploaions did not occur in
any case with temperatures above 65° C.
Sometime after this work was completed there appeared
an riif^lish patent #174,6351 in which it was stated that the
chlorination oi acetylene could be controlled in the presence
01 steam superheated to 400°-500° C.
Motmeyrat^ has studied the action of chlorine on acety-
lene. He states that ethylene dichloride in the presence of
aluminum chloride at 70°-75° decomposes to give acetylene
and hydrochloric acid
(1) C2H4CI2 > C2H2 + 2 HCl
He chlorinated C2H4CI2 under these conditions and got C2H2CI4.
Assuming that reaction (1) does take place he accounts for
the fact that no explosions occurred on chlorination by say-
ing that there was a total absence of oxygen. If the presence
of oxygen be the cause of the explosions then we would expect
that on passing the gases through water, the dissolved
oxygen would be expelled and that the explosions v/ould gradu-
ally cease. This, however, was not the case.
1. Chem. Abs. 16, 1779
2. Bull. soc. chim. 19, 448
Aftor the water had been stirred for one hour at a
temperature of 80° using 350 cc. of Clo and 1400 cc. of
C2H2 per minute, an emulsion was formed and very effective
stirring was taking place. A current of air had to bo
directed on the end of the exhaust pipe to prevent the
exhaust gases from igniting. The fact that the exliaust
gases after leaving the refl\r:c condenser would catch fire,
Wiiile no explosions were occurring in the reaction bottle
seeir.s to indicate that water vapor had a great influence
in preventing explosions in the chamber; ot that due to
the heating practically all of the oxygen was driven out.
Refluxing began at 76° C After two hours at the above
rates of flow the product was fractioned. Three drops of
a coloi-less oil, heavier than water, having a boiling point
at about 90° were obtained. This i)il has an odor which at
first is etherial but on further inhalation becomes ex-
tremely pxmgent. The odor was identical with that of di-
chloracetaldehyde. It is known that acetylene and water
react slightly to give acetaldehyde
CgHg + HgO — ^ CH3CHO
It is likely that a small amoimt of this compoiuid was formed,
which on chlorination gave dichlor-acetaldehyde.
After the water fraction had come over 50 g. of a color-
less, odorless oil, boiling at 109° and having a specific
gravity of 1.C889 was obtained. Theue physical duta do
not check with those of any of the compoirnds which could
THE CHLORIMTIOII OF ACiilTYLiillS
BY THE USE OF SULPHUS DICHLORIDE
Since acetylene coiild not be chlorinated under the
conditions as set forth above, work was undertaken to study
its chlorination by the use of sulphur dichloride according
to the method of I.Iichel-'- . This consists in alternately
passing chlorine and acetylene into a mixture of sulphur
monochloride and 2% hydrogen reduced iron. I.Iichel simply
allowed these gases to bubble through the mixture; he states
that a good yield of hexa-chlorethane can be obtained in
this waj^. The reactions v;hich take place are:
(1) SgClg + Clg -^ 2 SClg
(Z) CgHg ■\- 4 SClg -^CgHgCl^ +2 SgClg
(3) CgHg + 6 SClg -^CgClg + 3 SgClg
In the first experiment the temperature was so regu-
lated that gentle reflxrxing took place, oince the reaction
SgClg + Clg ^ 2 SClg
1. /ieit. Angew. Chem. 19, 1095
is exotherrdc and since fiirthor the 'boilinf? point of -jClg ,
which is being formed, is lower than that of SgClj), a
cooling coil was placed aroimd the reaction vessel and the
wliole immersed in an oil bath. The temperature at the begin-
ning was held at 125°. Chlorine was stirred into 1057 g.
of S2CI2 at a rate of 1500 cc. per minute for 10 minutes;
total absorption talcing place. At the end of this period
the entire contents of the reaction vessel was forced out
of the liquid seal witli exj-^losive violence. This could
have been d\ie to the instability of sulphur dichloride or
to the clogging of the exhaust line. The latter was found
not to have been the cause.
In the follov/ing experiments the temperature during
chlorinations was held at 40°; this seemed to help rather
than hinder the rate of chlorination. The absorption of
acetylene however occurred more rapidly at somewhat more
elevated temperatures. The heat liberated during the ab-
sorption 01 acetylene v/as used to raise the temperature
of the mixture to about 80° C.
It was not found necessary to remove the excess of
acetylene by means of an inert gas such as COg before a
The flow 01 chlorine was measured by a calibrated flow-
m.eter, the acetylene by means of a wet meter.
The chlorination of sulphur monochloride took place
with eictroue ease; it being possible to get 1299 g. of
the monochloride to absorb as high as 7000 cc. of chlorine
In the case oi' the absorption oi" acetylene the reac-
tion proceeded in a manner which is often found when work-
ing with catalysts, namely that the reaction had to gradual-
ly "build itself up". By this is meant that although at
the beginning the catalyst might be distributed throughout
the sulphur chloride medium rather homogeneously, the acety-
lene woiild not be taken up at the same rate at which it
would bo, after the reaction had been in progress for some-
time. The rate of absorption of acetylene wotLLd always in-
crease to a maximum and then gradually decrease. This
phenomenon is not to be explained as being due to the pres-
ence of small amounts of the chlorethanes, for even when they
were present at the beginning, the reaction exhibited the
same behavior. It is likely, however, that this behavior
can be explained as being due to the formation of an inter-
mediate compound betv/een Fe and CgHg; which compound later
catalizes the reaction.
After the reaction slowed down, the siilphur monochloride
was chlorinated to the dichloride and this was distilled off.
The remaining liquid was steam-distilled; this served to
carry off the liquid tetrachlorethane from the solid hexa-
chlorethane. In several experiments the sulphur chlorides
were decomposed with water, tlie liberated hydrochloric
acid neutralised with IJagCOg, and the mixture sterna-dis-
tilled. The residue consistinp of sulphur and hexachlor-
Qthane was then extracted with ether.
In order to get a closer estimate of the relative
yields, two runs were made and the resulting products were
worked up together.
Average rate of chlorination = 2920 cc. per nin. or
2.25 cc. Gig per g. S„C1„ per minute.
The averarre rate oi acetylene absorption = 1100 cc. per
minute, or 0.85 cc. CoHg per g. S^Clo per minute.
The relative rates of chlorine uptake to acetylene
uptake are apparently 3:1. V/eight of product z 1410 g.
RUII # E
934 g. S2CI0
25 g. ?e
Yield of mixture of C2H2CI2
The total products from "both runs amounted to 2445 g.
which on separation gave tiie lollowinr percentaf^e by weifjht.
It is qixite evident that this method gives only a very
small relative amount of hexachlorethane ; the main product
The tetrachlorethane thus prepared was further chlori-
nated to hexachlorethane in the presence of AICI3. This
procedure is similar to that used by Llouneyrat by which he
chlorinated ethylene dichloride to hexachlorethane.
The chlorine was passed into the mixture at 120° C. The
density increased with the chlorine absorption until a point
was reached where the entire contents of the hottle solidified
and could no longer be stirred. The hexachlor-ethane was freed
as much as possible from the tetraclilor-othane by suction and
the former then recrystallized from alcohol. The yield
of CgClg calculated upon the basis of the amoixnt of chlorine
used amounted to 63/i.
The effects of stirring: at a rate of 8000 K.P.LI. on the
rate or absorption of chlorino by tetruchlorethano in tho
presence of AICI3 was investigated at a point in the chlori-
nation where the chlorine was being taken up at a rate of
1400 CO. per minute. The stirring was stopped with the
result that the flow-meter pressure on the chlorine line
dropped from 3 cm. indicating a rate of 1400 cc. per minute
to 1 c:.:. indicating a rate of 750 cc. per minute. The latter
rate is necessarily greater than it would have been, had not
the liquid been previously stirred, since as soon as the
stirring was stopped the AlCl^ was still rather homogeneously
distributed throughout the liquid.
1. Chlorination of acetylene in the presence of 2%
catalytic iron gives s-tetrachlorethane almost exclusively.
E. s-Tetrachlorethane can be chlorinated in the presence
of AlCl^ using high speed stirring until the reaction mixture
solidifies, thus giving a yield of 63/0 hexachlorethane.
3. The effect of high speed stirring was to double the
rate of chlorination of s-tetrachlorethane to hexachlorethane.
4. Chlorine and acetylene may be made to react without
violence in the presence of water vapor above 65° C.
The author of this dissertation was born in Charles
Co., iJaryland, ii'ebruary 8, 1897. He received his early
education in the public schools of Baltimore and graduated
from The .JOhns Hopkins University in 1920 with the degree
of Bachelor of Science. In the fall of 19E0 he entered the
Johns Hopkins Graduate School of Ghe;nistry, taking as his
subordinate subjects rhysical uhemistry and -lathematics .
In June 1922 he received the degree of ..iaster of Arts, the
title of his thesis being:- "The Friedel and Orafts Reaction.
During the years 1921-22 and 1922-23 he was part-time
instructor in Organic Chemistry at the Mt. 7ernon College of
Baltimore and the University of Maryland respectively.
He was appointed a Hopkins Scholar for the years 1920-
21. 1921-22 and 1922-23.