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Organic syntheses - Roger A.

Roger A. Organic syntheses - Chapman, 1936. - 110 p.
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bromostyrene or styrene dibromide. Vaughn, ibid. 56 2069 (1934).
By the action of a solution of sodamide in liquid ammonia upon /3-
bromostyrene, a-chlorostyrene, or styrene dibromide. Vaughn, Vogt, and
Niecwland, ibid. 56, 2120 (1934).
Phenylethylene (Coll. Vol. i, 430): In 75-80 per cent yield by
a-chloroethyl benzene with a small excess of quinoline; in 75 per cent
yield by heating a-phenylethyl alcohol with 3-5 per cent of potassium
bisulfate. Zal'kind, Berkovich, and Amusin, Plastichesfcie Massui 1934,
No. 1, 14 [C. A. 28, 5810 (i934)].
In 93 per cent yield by heating a-phenylethyl alcohol with 5 per cent
of sodium or potassium bisulfite. Gauthier and Gauthier, Bull. soc. chim.
[4I 53, 323 (1933).
Pbenylglyoxal (15, 67): Preparation and use of selenium dioxide for
oxidations. Hahn and Schales, Ber. 67, 1823 (1934); Riley, U. S. pat.
1,955,890 [C. A. 28, 4067 (1934)].
Platinum Catalyst for Reductions (Coll. Vol. 1, 452): Directions are
given for the preparation of a colloidal platinum (or palladium) catalyst
in an anhydrous, alkaline medium. This catalyst is said to be
particularly valuable for the reduction of nitriles, oximes, and
nitrostyrenes to pure primary amines. Skita and Keil, Ber. 63, 424
Quinizarin (Coll. Vol. 1, 464): From atithraquinone by reaction with
nitro-sylsulfuric acid in the presence of small amounts of mercury. U. S.
pat. 1,963,136 [C. A. 28, 5079 (1934)].
Quinoline (Coll. Vol. i, 456): The Skraup synthesis is carried out
with fuming sulfuric acid and copper sulfate catalyst, at 135-154.
Kirkhgot and Zasosov, Khim. Farm. Prom. 1934, No. x, 40 [C. A. 28, 5454
Trinitrobenzene (Coll. Vol. 1, 526): Preparation from 2,4,6-
acid, or 2,4,6-trinitrobenzaldehyde. Secareanu. Bull. soc. chim. [4] 53,
1395 (A934).
Veratric Aldehyde (13,102): By methylation of vanillin with methyl p-
toluene-sulfonate. Kanevska, Arch. Pharm. 271, 462 (1933).
(The numbers in parentheses following the name of the compound refer
to the volume and page of Organic Syntheses. New methods or changes in
procedure have not been checked unless otherwise noted.)
Benzyl Cyanide (Coll. Vol. i, 101):
Benzyl isocyanide, which gives the product a disagreeable odor, can
be removed completely by washing the crude material after the first
distillation with an equal volume of warm (6o) 50 per cent sulfuric
acid, prepared by adding 275 cc. of concentrated sulfuric acid to 500 cc.
of water. The benzyl cyanide is shaken vigorously for about five minutes
with the acid, separated, and washed with an equal volume of saturated
sodium bicarbonate solution, followed by an equal volume of half-
saturated sodium chloride solution. After drying and distilling under
reduced pressure, the product is water-white and remains so after
standing for several months. The loss in the washing operations is
negligible, and the yields are the same as those reported previously.
John R. Johnson, private communication.
Ethyl Benzoylformate (Coll. Vol. 1, 236):
By a slight modification of the procedure, crystalline benzoyl-formic
acid (phenylglyoxylic acid) can be isolated. The oxidation of 375 g. (2.5
moles) of mandelic acid by cold alkaline potassium permanganate is
performed exactly as described in the first paragraph (p. 236). After
removal of the manganese dioxide, the combined filtrates are evaporated
to 2500-3000 cc., rather than 800-1000 cc. as given in the second
paragraph (p. 237). At this point the solution is acidified carefully, so
as to precipitate only benzoic acid, by the addition of 100 cc. (190 g.)
of concentrated sulfuric acid (sp. gr. 1.84) previously diluted with an
equal volume of water and cooled. The benzoic acid (25-30 g.) which
separates is removed by filtration. The filtrate is made alkaline with
75 g. of sodium hydroxide and concentrated to 800-1000 cc. The subsequent
acidification, with 280-300 cc. of concentrated sulfuric acid, and ether
extraction are performed as described in the third paragraph (p. 237).
After removing the ether about 280 g. of crude, liquid benzoylformic add
remains; at this stage enough water is present to render the acid
immiscible with carbon disulfide.
The liquid residue is dried by placing it in a distilling flask with
70-90 cc. of toluene, and distilling off the water and toluene
(preferably under slightly reduced pressure). The dried liquid residue is
taken up in an equal volume of carbon disulfide; with adequate
precautions to exdude moisture, the solution is cooled thoroughly in an
ice-salt mixture. The yield of product melting at 58-61 is 190-250 g.
(50-67 per cent of the theoretical amount).
Charles D. Hurd and R. W. McNamee, private communication. Checked by
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