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Orthotolylstibine is a thick liquid, and forms a crystalline
bromide. 2

1 Michaelis and Genzken, Ber. Deutsch. Cliem. Gcs. xvii. 924.

2 Ibid.



MERCURY DERIVATIVES OF TOLUENE. 87



BORON AND SILICON DERIVATIVES OF
TOLUENE.

2062 Paratolylboron chloride, CH 3 .C 6 H 4 BCL, is obtained by
the action of boron chloride on mercury paratolyl, and is a
colourless crystalline mass, which melts at 27. Water converts
it into tolylboric acid, CH 3 .C 6 H 4 B(OH) 2 , a violent reaction
taking place ; this compound crystallizes from hot water in fine
needles melting at 240 . 1

Paratolyhilicon chloride, CH 3 .C 6 H 4 SiCl 3 , is obtained by heating
mercury tolyl with silicon tetrachloride to 300 320. It is a
strongly refractive liquid which boils at 218 220, fumes in
the air and is converted by dilute ammonia into paratolyl silicic
acid, CH 3 .C 6 H 4 SiO(OH), which separates from ether as an oil
which gradually changes into a thick, elastic mass. It commences
to lose water at 100 and is completely converted at 200 into
paratolylsilicon oxide, which is a solid mass. 2

Silicon paratolyl, Si(C 6 H 4 .CH 3 ) 4 , is readily obtained by the
action of sodium on a mixture of silicon chloride and parabromo-
toluene. It separates from benzene in transparent crystals
melting at 228, and boils above 360 without decomposition. 3

Dichlorosilicon orthoditoluide, SiCl 2 (NH.C 7 H 7 ) 2 , is formed by
the action of silicon tetrachloride on orthotoluidine. It forms a
colourless, amorphous mass which readily absorbs moisture with
formation of silica and toluidine hydrochloride. Hydrochloric
acid gas decomposes it into toluidine hydrochloride and silicon
tetrachloride. 4



MERCURY DERIVATIVES OF TOLUENE.

2063 Dreher and Otto obtained mercury paratolyl by the
action of sodium amalgam on the bromotoluene obtained by the
direct bromination of toluene. 5 Ladenburg then showed that
the ortho-compound is also formed in this way and can readily be

1 Michaelis and Becker, ibid. xv. 185.

- Ladenburg, Ann. Ch-em. Phann. clxxiii. 162.

3 Polis, Bcr. De,utsch. Chcm. Gcs. xviii. 1542.

4 Harden, Jou.rn. Chem. Soc. 188", 44. s Ann. Chsm. Pharm. cliv. 171.



AROMATIC COMPOUNDS.



separated from the para-compound by re-crystallization from
benzene. 1 In order to prepare it, bromotoluene to which a little
acetic ether and petroleum have been added, is boiled with
1-5 per cent, sodium amalgam for a longtime in an apparatus
connected with an inverted condenser, and the products separated
by re-crystallization from hot benzene. 2

Mercury orthotolyl, (CH 3 C 6 H 4 ) 2 Hg, is more readily soluble
in benzene than the para-compound and crystallizes in large
triclinic tablets melting at 107.

Mercury paratolyl forms matted needles which melt at 238
and can be distilled without decomposition, if the heating be
very carefully performed. It is only slightly soluble in cold
water. Its derivatives resemble those of mercury phenyl.

1 Ann. Chem. Pharm. clxxiii. 162. 2 Ibid. cci. 246



BENZYL GROUP.

2064 The compounds obtained by the replacement of one
atom of hydrogen in the methyl group of toluene by other
elements or radicals are looked upon as derivatives of a mono-
valcnt radical phenylmethyl or benzyl, C 6 H 5 .CH 2 .



BENZYL ALCOHOL, C 6 H 5 .CH 2 .OH.

Liebig and Wohler, in 1832, observed that when oil of bitter
almonds, C 7 H 6 O, is treated with alcoholic potash in absence of air,
benzoic acid, C 7 H 6 2 , is formed, together with an oily substance,
which is different from the original oil ; they make the following
remarks : " Although we have not investigated this new product
more carefully, there can be no doubt, provided that the alcohol
takes no essential part in the reaction, that it is formed either by
separation of oxygen from the oil of bitter almonds or by some
reaction involving the sharing of the elements of water. In the
former case its composition will be expressed by the formula
C U H 12 0, in the latter by C 14 H 14 O 2 " l (C = 6, O = 8 ).

Cannizzaro then found that this substance is " the alcohol
corresponding to benzoic acid," and that although its composition
does not correspond with that of the ordinary alcohols, it behaves
towards reagents as an alcohol, the aldehyde of which would be oil
of bitter almonds. He obtained the latter compound by oxidizing
the alcohol with ordinary nitric acid, while chromic acid gave
benzoic acid. He further showed that the action of hydrochloric
acid produced an ethereal chlorine compound, C 7 H 7 C1, which is
derived from the alcohol of benzoic acid and is reconverted into
the alcohol by treatment with caustic potash ; when heated with
alcoholic ammonia it yielded a base which differed essentially

1 Ann. Chem. Pharm. iii. 254, 261.



90 AROMATIC COMPOUNDS.

from toluidine. He also prepared the acetate, which is decom-
posed by warming witli caustic potash into acetic acid and the
alcohol of benzoic acid, and says : " This kind of alcohol appears
to be the type of a whole class of new alcohols, the more complete
investigation of which is now in progress." l

In the course of. this investigation he found that concentrated
alcoholic potash produced a decomposition in which benzoic acid
and toluene were formed from the alcohol, so that the latter
stands in the same relation to toluene as wood-spirit to marsh
gas: 2 .

C 7 H 8 0-+ KOH = C 7 H 5 K0 2 + 2H 2

C 7 H 8 + H 2 = C 7 H 8 + H 2 0.

He also succeeded in converting toluene into the alcohol ; by
the action of chlorine on the boiling hydrocarbon he obtained
chlorobenzyl, which was identical with that obtained by the
action of hydrochloric acid on the alcohol. On heating with
potassium acetate, both compounds gave benzyl acetate, which
yielded the alcohol on saponification with caustic potash. 3

This compound had previously been in the hands of several
chemists, who had not, however, recognised its nature. Fremy
isolated from Peru balsam a compound which he named cinnamein,
from which he obtained cinnamic acid and peruvin, C 9 H 12 O, by
heating with caustic potash. 4 The latter compound, according
to Plantamour, who prepared it the same way and also observed
the formation of cinnamic acid, is ethyl cinnamate ; he was led
to this conclusion by the fact that when he heated it with
caustic potash and evaporated the whole to dryness, he obtained
potassium cinnamate and a combustible vapour which he took
for ethyl alcohol. He remarks that the origin of this substance,
which was only recognised in this indirect and remarkable
manner, still requires explanation. 5 Scharling first accurately
determined the composition of cinnamein and looked upon it as
a compound ether. The peruvin, C 7 H 8 O, obtained from it he
considered as an alcohol, probably identical with Cannizzaro's
compound. When he brought it into contact with platinum
black, the smell of oil of bitter almonds was produced. 6

Strecker then expressed his conviction that cinnamein is the
cinnamic ether of benzyl alcohol, 7 and was confirmed by Kraut,

1 Ann. Chem. Pharm. Ixxxviii. 129. 2 Ibid. xc. 252.

J {^ x cvi. 246. 4 Ibid . xxx. 324.

Ibid. xxx. 341. 6 j bid . xcvii. 168.
7 Lehrb. Org. Chem. 1856, 456.



BENZYL COMPOUNDS. 91

according to whom Fremy's peruvin was a mixture of this
alcohol and toluene, Plantamour's compound being, however,
the pure alcohol. The acid taken for cinnamic acid was
obviously benzoic acid and the combustible vapour consisted of
toluene. 1

The liquid portion of Peru balsam 2 consists chiefly of the
benzoate and cinnamate of benzyl, but also contains some free
benzyl alcohol. 3 Both ethereal salts occur in Tolu balsam, 4 and
the latter in liquid styrax. 5

Benzyl alcohol also seems to be contained in the oil of the
cherry-laurel, which consists chiefly of benzaldehyde and its
cyanhydrin (Tilden). 6

The action of alcoholic potash on oil of bitter almonds, which
was observed by Cannizzaro, is characteristic of the aromatic
aldehydes, oxidation and reduction taking place simultaneously :

C 6 H 5 .CHO + KOH = C 6 H 5 .CO.OK + H 2
C 6 H 5 .CHO + H 2 = C 6 H 5 .CH 2 .OH.

Benzyl alcohol is also formed by the action of sodium amalgam
and water on benzaldehyde 7 and on benzoic acid, 8 while the
fatty acids are not changed by nascent hydrogen. Benzoyl
chloride, C 6 H 5 .COC1, is also reduced to benzyl alcohol by the
action of sodium amalgam and hydrochloric acid, 9 while a better
yield may be obtained by adding sodium amalgam to an ethereal
solution of benzamide, C 6 H 5 .CONH 2 , which contains water and
has been rendered faintly acid with hydrochloric acid. 10

1 Ann. Chem. Pharm. cvii. 208.

- Peru balsam, like Tolu balsam, was first described by the Spanish physician
Monardes (p. 3) ; the latter is derived from Myroxylon toluifera, the former from
Myroxylon pareirae, a native of Central America in the district of Costa del
Balsamo. Peru balsam contains the same substances as that from Tolu, together
with several of a different nature, this being due to the difference in the methods of
extraction employed in the two cases. While the latter is obtained by the simple
process of making incisions, it is necessary to remove the bark before extracting the
Peru balsam. In order to accomplish this, it is first loosened by blows of a hammer
or the back of a?i axe, and is then superficially charred by burning torches or
bundles of twigs, the effect of this treatment being either to detach it or to render
its removal a matter of no difficulty. The stem is next wrapped round with rags,
which become saturated with the balsam, and are then removed and heated with
water ; the balsam is thus separated from the cloth and sinks to the bottom of the
vessel (Fliickiger and Hanbury, Phannacographia, 2 Ed. p. 205).

Kraut, Ann. Chem. Pharm. clii. 131.

Ber. Dcutsch. Chem. Ge*. ix. 830.

Laubenheimer, Ann. Chem. Pharm. clxiv. 289.

Pharm. Journ. Trans. [3] v. 761.

Friedel, Ann. Chem. Pharm. cxxiv. 324.

Herrmann, ibid, cxxxii. 75. 9 Lippmann, ibid, cxxxvii. 252.

Guareschi, Gazz. Chim. Ital. iv. 465 ; ftcr. Deutsch. Chem. Gc*. vii. 1462.



92 AROMATIC COMPOUNDS.

It is best obtained from benzyl chloride, which can readily be
prepared from toluene, by boiling it for two hours with water and
lead hydroxide, 1 or by simply boiling it for two days with
25 30 parts of water, 76 per cent, of the theoretical yield being
thus obtained. 2

According to Mennier, it may be advantageously prepared by
boiling equal parts of benzyl chloride and potassium carbonate
with 10 parts of water for several hours. 3

Cannizzaro's process does not serve for the preparation of the
alcohol from benzaldehyde, as the action of the alcoholic potash
is only gradual, even on long continued heating, and a consi-
derable loss is experienced through the formation of resinous
products. If, however, 10 parts of the aldehyde be shaken
up with a solution of 9 parts of caustic potash in 6 parts of
water until a permanent emulsion is obtained, and sufficient
water to form a clear solution be then added to the semi-solid
mass of crystals formed on standing by the separation of potas-
.sium benzoate, the benzyl alcohol can readily be extracted from
the liquid with ether. The ether is then distilled off and the
residue purified by rectification without being dried. In this
way 92 per cent, of the theoretical yield can be obtained, while
the application of alcoholic potash only gives a yield of 43 per
cent. Since only one half of the benzaldehyde is converted into
the alcohol, benzyl chloride is a more economical source ; it is,
however, more difficult to obtain in a state of purity than
benzaldehyde and therefore does not yield a pure product so
readily. As mentioned above, it is impossible to dry the
alcohol before distillation; it combines with calcium chloride
slowly in the cold, more rapidly on heating, and is attacked by
solid caustic potash. 4

If two molecules of benzaldehyde be added to a solution of
one atom of sodium in 12 parts of methyl alcohol and the mixture
heated in an apparatus connected with inverted condenser, a white
substance soon separates out, which seems to be a compound
of methyl benzoate and sodium methylate, since it is formed
when these are heated together. If the heating be continued
for about two days and the mass neutralized with glacial acetic
acid, and then heated with water, an oil separates out which can

1 Grimaux and Lauth, Ann. Chem. Pharm. cxliii. 80.
1 Niederist, ibid, cxcvi. 353.

* Bull. Soc. Chim. xxxviii. 159.

* ]{. Meyer, Ber. Dcutsch. Chcm. Got. xix. 2394.



BENZYL ALCOHOL. 93



be separated into two portions by distillation. About two-thirds
of the whole boil between 198 210, and consist of a mix-
ture of equal molecules of methyl benzoate, boiling at 199,
and benzyl alcohol, boiling at 206. These cannot be separated,
but if the benzoate be saponified, pure benzyl alcohol can
readily be obtained.

The smaller portion of the product, about 20 30 per cent.
on the benzaldehyde employed, boils at 320 324, and consists
of benzyl benzoate. This is polymeric with the aldehyde and is
formed directly from it :



C 6 H 5 -CHO CgHs-CO/

The chief reaction, however, consists in the conversion of the
benzaldehyde in the presence of sodium methylate into methyl
benzoate and benzyl alcohol :

2C 6 H 5 .CHO + CH 3 .OH = C 6 H 5 .CO.OCH 3 + C 6 H 5 .CH 2 .OH.

The two latter appear to be then partially converted into
benzyl benzoate and methyl alcohol. 1

If this reaction be employed for the preparation of benzyl
alcohol, the original product is simply saponified.

In order to prepare it from Peru balsam, the latter is thoroughly
agitated with 2 volumes of caustic potash of sp. gr. 1'2, the
emulsion exhausted with ether, the extract separated and eva-
porated, and the residual oil heated with 4 volumes of caustic
potash of sp. gr. 1*3 until a homogeneous liquid is obtained. The
pulpy mass of crystals formed on cooling is pressed in linen,
and the liquid diluted with water and distilled until the dis-
tillate ceases to appear milky. The alcohol is then separated
from the aqueous distillate and the portion which remains dis-
solved in the latter extracted by ether. 2

Properties. Benzyl alcohol is a liquid which possesses a faint
aromatic odour, boils at 206, and has a sp. gr. of T063 at 0.
It is not insoluble in water, as was at one time thought, for
100 parts of water at 17 dissolve 4 parts (R Meyer). When
heated with hydriodic acid and a little phosphorus to 170
180, it is almost completely reduced to toluene, only a small



1 L. Claisen, private communication.

2 Kachler, Bcr. Df.utech. Chem. Got. ii.



512.



94 AROMATIC COMPOUNDS.

amount of higher boiling substances being formed. 1 Its other
characteristic properties which were ascertained by Cannizzaro
have been already mentioned.



BENZYL ETHERS.

2065 Benzyl methyl ether, C 6 H 5 .CH 2 .O.CH 3 , was obtained by
Sintenis by heating benzyl chloride with methyl alcohol and
caustic potash. 2 It is a pleasant smelling liquid, which boils
at 167 168 and is decomposed by chlorine in the cold with
formation of benzaldehyde and methyl" chloride :

C 6 H 5 .CH 2 .O.CH 3 + C1 2 = C 6 H 5 .COH + CH 3 C1 + HC1.

Benzyl ethyl ether, C a H 5 .CH 2 .O.C 2 H 5 , is formed when benzyl
chloride is boiled with alcoholic potash, and is a mobile liquid,
possessing a pleasant odour and boiling at 182 184 . 3 Chlorine
acts upon it in the cold just as on the methyl ether ; at the
boiling point, however, benzoyl chloride is formed :

C 6 H 5 .CH 2 .O.C 2 H 5 + 2C1 2 = C 6 H 5 .COC1 + C 2 H 5 C1 4- 2HCL

In the presence of iodine, ethyl iodide and parachlorobenz-
aldehyde, C 6 H 4 C1.COH, are obtained (Sintenis).

Bromine produces a similar decomposition, benzaldehyde, ethyl
bromide and hydrobromic acid being first formed ; the latter
then decomposes another portion of the ether into benzyl
bromide and ethyl bromide, and the benzaldehyde is converted
into benzoyl bromide by the excess of bromine. 4

Dibenzyl ether or Benzyl oxide, (C 6 H 5 .CH 2 ) 2 O. Cannizzaro
obtained this compound by heating benzyl alcohol to 120 125
with boron trioxide and treating the product with water and
potassium carbonate. When the dried oil is distilled, unaltered
benzyl alcohol comes over first, and then the ether, a resinous
hydrocarbon remaining behind in the retort. According to
Lowe B dibenzyl ether is best prepared by the action of benzyl
chloride on sodium benzylate in the following manner : Sodium

1 Grabe, Ber. Deutsch. Chem. Gcs. viii. 1054.

2 Ann. Chem. Pharm. clxi. 334.

3 Cannizzaro, Jahresb. 1856, 582.

4 Paterno, Oaz. Chim. Ital. i. 586.

5 Ann. Chem. Pharm. ccxli. 374.



BENZYL ETHERS. 95



is added to benzyl alcohol diluted with ether, heat being finally
employed to obtain complete solution of the sodium ; benzyl
chlorine is then added and the mixture gently heated, a some-
what violent reaction taking place.

Cannizzaro describes dibenzyl ether as a colourless oily liquid
which boils at 310 315, and has a faint indigo-blue fluores-
cence ; it decomposes into toluene and benzaldehyde when
heated to -a few degrees above 315 in a sealed tube, a small
quantity of the resinous hydrocarbon being likewise formed.
Lowe finds that dibenzyl ether is colourless and shows no flu-
orescence, has a slight but persistent odour of hawthorn blossom,
and boils at 295 298, being partially resolved at the same
time into toluene and benzaldehyde. At 315 this decomposition,
as found by Cannizarro is much more rapid.

Dibenzyl ether is also formed in small quantity, together
with various hydrocarbons, when benzyl chloride is heated with
water to 190 . 1

Benzyl phenyl ether, C 6 H 6 .CH 2 .O.C 6 H 5 , is obtained by heating
benzyl chloride with potassium phenate and alcohol to 100 . 2
It forms scaly crystals with a nacreous lustre, melts at 38 39
and boils at 286 287 (Sintenis). On heating with con-
centrated hydrochloric acid to 100, it decomposes into benzyl
chloride and phenol ; hydrobromic acid produces a similar
decomposition. Chlorine attacks it in the cold with formation
of benzyl chloride and substitution products of phenol, the
action of bromine being quite analogous. In the presence of
mercuric oxide, on the other hand, substitution products of the
ether are formed (Sintenis).

Melting- Boiling-
point. point.

Benzyl chloro- j C,H,.CH, \ . .
phenyl ether J *C&d \ lon g needles 70-71
Benzyl bromo- ) C R H,.CH 9 ) ~ ,
phenyl ether } 6 C 6 H 4 Br \ lon ^ needles 59 ~ 59 '
Benzyl ortho- ) CLH K .CH. ) ~ ,.
cresl e 3 liqmd 285'-290"



cresyl ether 3 }ccj

Benzyl para- | C 6 H 5 .CH 2 n hexagonal ) ,,
cresyl ether ]CH 3 .C 6 H 4 f U prisms f*

Ethers of benzyl with the dihydroxylenzenes are formed when



1 Limpricht, Ann. Chem. Fharm. cxxxix. 307.

- Lauth and Grimaux, ibid, cxliii. 81.

3 Stadel, Bcr. Deutsch. Chem. Ges. xiv. 898.



96 AROMATIC COMPOUNDS.

the latter are heated with benzyl bromide and alcoholic



Melting-
point.



. . nTT fOH \large lustrous")

Benzylqumol, O 6 H 4 j OfCSfC ^ ] sca les

Dibenzylquinol, C 6 H 4 (O.CH 2 .C 6 H 5 ) 2 , lustrous tablets 130

Dibenzylresor- ) P TT / n PTT r TT N / small lustrous } 7fi
cinol, } C 6 H 4 (O.CH 2 .C 6 H 5 ) 2 , | tabletg j

} C 6 H 4 (O.CH 2 .C 6 H 5 ) 2 , yellow needles 61



ETHEREAL SALTS OF BENZYL.

2066 Benzyl chloride, C 6 H 5 .CH 2 C1. Cannizzaro obtained this
compound by the action of hydrochloric acid on benzyl alcohol
and it is also formed by that of chlorine on boiling toluene. 2

It is prepared on the large scale by the latter method, the
toluene being contained in large glass balloons heated by a bath
of calcium chloride, and the chlorine passed through in such a
manner that it chiefly comes in contact with the vapour of the
toluene. This is effected by only allowing the leaden conducting
tube, which terminates in a short piece of glass tubing, to dip a
small distance below the surface of the boiling liquid. The
vapours of toluene are condensed by a cooling arrangement
and the hydrochloric acid evolved is led into water. The
product is washed with water containing a little caustic soda,
and the benzyl chloride freed from unaltered toluene and
higher substitution products by distillation.

It is a colourless liquid, the vapour of which has a penetrating
aromatic smell, rapidly produces a flow of tears and attacks
the mucous membrane most violently. It boils at 176 and
has a sp. gr. of 1*107 at 14. As it undergoes double decom-
position very readily, it is employed for the preparation of the
other benzyl compounds, and it is also used to a considerable
extent in the synthesis of the higher members of the aromatic
series. It is also technically employed in the manufacture of
benzaldehyde and in the colour industry.

1 Schiff and Pellizzari, Ann. Chem. Pharm. ccxxi. 365.
* Beilstein and Geitner, ibid, cxxxix. 337.



BENZYL IODIDE. 97



Benzyl bromide, C 6 H 5 .CH 2 Br, is formed by the action of
hydrobromic acid on benzyl alcohol, and by that of bromine on
boiling toluene. 1 It is a liquid which first smells like cress and
then like mustard oil ; its vapour, like that of the chloride, pro-
duces a flow of tears. It boils at 198 199, and has a sp. gr.
of 1-438 at 22.

Benzyl iodide, C 6 H 5 .CH 2 I, was obtained by Cannizzaro in the
impure state by the action of iodine and phosphorus on benzyl
alcohol. Lieben prepared the pure compound by allowing benzyl
chloride to stand in the dark for three weeks with five times its
weight of hydriodic acid. 2 It is also formed by the action of
potassium iodide on benzyl chloride, 3 and is a colourless, crystal-
line body, the vapour of which produces a most copious flow
of tears; it is only slightly soluble in alcohol, but readily in
ether and carbon disulphide. It fuses at 24 to a liquid which
has a sp. gr. of 1'7335, and on further heating becomes coloured
red, decomposing at about 240, at which temperature it com-
mences to boil, into iodine, hydriodic acid, and a hydrocarbon
which smells like toluene.

Benzyl nitrate, C 6 H 5 .CH 2 .NO 3 . appears to be formed by the
action of silver nitrate on benzyl chloride : the product of the
reaction decomposes on distillation with an energetic evolution
of red fumes, the distillate consisting of benzaldehyde and
benzoic acid. 4

The same products are obtained by treating benzyl iodide
with silver nitrite. 5

2067 Benzyl acetate, C 6 H 5 .CH 2 C 2 H 3 O 2 . Cannizzaro obtained
this compound by distilling benzyl alcohol with acetic and
sulphuric acids, as well as by heating benzyl chloride with
potassium acetate, and alcohol. It is a liquid which possesses
an aromatic odour, boils at 206, and has a sp. gr. of T057 at
16'5. 6 It is converted into the benzyl ether of hydrocinnamic
acid or benzylacetic acid by the action of sodium :
4C 6 H 5 .CH 2 .O.CO.CH 3 +2Na =
2C 6 H 5 .CH 2 .O.CO.CH 2 .CH 2 .C c H 5 +2NaO.CO.CH 3 +H 2 .

Boiling-point.

Benzyl propionate, 0^.0.0^0 219 220.

Benzyl butyrate, C 7 H 7 .OC 4 H 7 O 238 240.

1 Kekule, Ann. Chem. Pharm. cxxxvii. 139 ; Cannizzaro, ibid. cxli. 198 ;
Beilstein, ibid, cxliii. 369 ; Lauth and Grimaux, ibid. cxlv. 113.

2 Zeitschr. C/iem. [2] vi. 736. 3 V. Meyer, Bcr. Dcutsch. Chem. Ges. x. 311.
4 Brunner, Bcr. Deutsch. Chem. Gcs. ix. 1744. 6 van Renesse, ibid. ix. 1454.
6 Conrad and Hodgkinson, Ann. Chem. I'harm. cxciii. 298.

VOL. III. PART IV. II



AROMATIC COMPOUNDS.



These ethers are acted upon by sodium in the same way as the
acetate (Conrad and Hodglunson). The compounds thus formed
will be subsequently described.

Benzyl oxalaie, (C 6 H 5 .CH 2 ) 2 C 2 O 4 , is formed by the action of
benzyl chloride on silver oxalate, 1 and by heating benzyl alcohol
with oxalic acid. 2 It crystallizes from hot alcohol in lustrous
white, scaly crystals, melting at 80'5.

honitrosobenzyl ether, C 6 H 5 .CH 2 .O.N==CH.CO.CH 3 , is prepared
by heating benzyl chloride with a solution of sodium and
isonitroso-acetone (Part I. p. 572, and Part III. p. 170, note) in
absolute alcohol. It crystallizes from petroleum ether in
colourless tablets, which have a pleasant smell of flowers and
melt at 45 4G. 3

Acetoxime benzyl ether, C 6 H 5 .CH 2 .ON C(CH 3 ) 2 , is obtained
in a similar manner from acetoxime, and is a pleasant smelling
liquid which decomposes into acetone and benzylhydroxylamine
when boiled with concentrated hydrochloric acid :

C 6 H 5 .CH 2 .O.N=C(CH 3 ) 2 +H 2 OrrC 6 H 5 .CH 2 .O.NH 2 +CO(CH 3 ) 2 .

The compound actually obtained in this way is lenzylhydroxy-
ammonium chloride, which crystallizes in silvery scales, and
is converted into benzyl iodide by heating with hydriodic



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