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Organic syntheses - Roger A.

Roger A. Organic syntheses - Chapman, 1936. - 110 p.
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alcohol, it is grossly inaccurate to estimate the amount of formaldehyde
present by reference to specific gravity tables (cf. Org. Syn. 14, 92).
The formaldehyde content of the solution is determined by analysis, for
which the iodimetric method of Borgstrom and Horsch5 is recommended. The
yield is calculated upon the basis of the amount of formaldehyde actually
present, as shown by analysis.
Fig. 3
2. Notes
2. A tall cylindrical vessel insures good contact between the
solution and the gas bubbling through it. Hydrogen sulfide from a
commercial cylinder was used.
3. Successful use of the inverted filtration method requires
attention to these details: (a) use of a sufficiently wide transfe tube;
(b) minimum exposure of tubing between the flasks; (c) rapid transfer of
the hot solution; (d) avoidance of too strong an application of suction.
The inverted filtration device is convenient for simple
recrystallizations as well as repeated extractions. It is of particular
advantage for the manipulation of volatile, inflammable solvents and of
lachrymatory solutions.
3. Methods of Preparation
rym.-Trithiane has been prepared by treating carbon bisulfide,1
ethyl isothiocyanate,2 or potassium thiocyanate2 with zinc and
hydrochloric acid; by heating methylene iodide with alcoholic sodium
hydrosulfide;3 and by treating aqueous formaldehyde with hydrogen sulfide
and concentrated hydrochloric acid.4
1 Girard, Compt. rend. 43, 96 (i856)[Ann. 100, 306 (1856)).
2 Hofmann, Aaa. 1, 176, 179 (1868).
3 Husemann, Ann. 126, 293 (1863).
'Hofmann, ibid., 145, 360 (1868); Baumann, Ber. 23, 67 (1890).
6 Borgstrom and Horsch, J. Am. Chem. Soc. 45, 1493 (1923).
(The following references are to methods of possible preparative
value that have been described recently. The numbers in parentheses
following the name of the compound refer to the volume and page of
Organic Syntheses.)
Allyl Alcohol (Coll. Vol. i, 34): By passing propylene oxide over
activated alumina at 2oo°-4oo°. Can. pat. 328,050 [C. A. 27, 1012
Allyl Cyanide (Coll. Vol. 1, 38): From allyl chloride and cuprous
cyanide, Faxaise and Frognier, Bull. soc. chim. Belg. 42, 427 (1933)
[Chem. Zentr. 105,
I, 529 (i934)]-
Arsanffic Acid (Coll. Vol. 1, 63): Reduction of the salts of
nitroarylarsonic acids in the presence of a nickel catalyst. Inotje and
Kimura, J. Pharm. Soc. Japan S3, 1105 (1933) [C. A. 28,3391 (1934)];
Stevinson and Hamilton, J. Am. Chem. Soc. 57, 1298 (1935).
Benzanthrone (15, 4): In 90 per cent yield by reducing anthraquinone
with a mixture of nine parts copper turnings and one part zinc dust, and
carrying out the condensation with glycerol and sulfuric acid at 105-
108°. Lukin, Anilino-krasochnaya Prom. 1931, No. 11-12, 14 [C. A. 28,
5241 (A934)].
Benzil (Coll. Vol. 1, 80): By heating benzoin with aniline and
aniline hydrochloride, in 75 per cent yield. Pandalai, J. Indian Chem.
Soc. 11, 511 (1934) [C. A. 28, 7256 (1934)]-
Benzohydrol (Coll. Vol. 1, 84): In almost quantitative yield by the
photochemical reduction of benzophenone in the presence of iio-propyl
alcohol and sodium zso-propoxide. Bachmann, J. Am. Chem. Soc. 55, 393
Benzophenone (Coll. Vol. 1, 89): By the rapid addition of
phenylmagnesium halides to one equivalent of benzoyl chloride. In one-
tenth mole experiments using phenylmagnesium iodide, bromide, and
chloride, the yields reported are 68, 55, and 48 per cent, respectively.
Gilman and Mayhue, Rec. trav. chim. 51, 47 (1932).
/C-Benzoylpropionic Acid (13, 12): From phenylmagnesium bromide
succinic anhydride. Kompfa and Rohkman, Ann. 509, 259 (1934).
Benzyl Cyanide (Coll. Vol. 1, roi): Preparation from mandelonitrile
in 79 per cent yield by catalytic reduction. Zelinsky, Packendoktf, and
Leder-Packen-dortf, Ber. 67, 300 (1934).
/'-Bromodlphenyl (Coll. Vol. 1, 109): From /'-dibromobenzene,
cyclohexanone, and activated magnesium, by a series of reactions
involving the formation and dehydrogenation of i-bromo-4-
cyclohexenylbenzene. v. Braun, Irmisch, and Nelles, Ber. 66, A471 (1933).
iio-Butyl Bromide (13, 20): Parallel experiments with fco-butyl and
other alcohols showed that with theoretical amounts of phosphorus
tribromide the yield
of alkyl bromide is ? per cent higher than with corresponding amounts
of red phosphorus and bromine. Tseng and Hon, J. Chinese Chem. Soc. 2, 57
e-Butyryl Chloride (Coll. Vol. 1, 142): Systematic study of the
preparation, using phosphorus pentachloride, phosphorus trichloride, and
thionyl chloride. Ciahx and Bell, Trans. Roy. Soc. Canada [3] 27, 97
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