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Organic syntheses vol 22 - Smith L.I.

Smith L.I., Adkins H. Organic syntheses vol 22 - John Willey, 1942. - 60 p.
Download (direct link): organicsynthesesvol221942.pdf
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2. Notes
1. Frequently the solution develops a blue color. If this persists, a little additional sodium hydroxide solution is required.
2. The yield (per cent) is the same if twice the amounts given are used. It is convenient to combine several runs for the reduction.
3. Sometimes the reduction does not start readily. If this is t lie case, the beaker may be cautiously heated, but provision for rapid cooling should be made.
4. Filtration is facilitated by use of a Pyrex glass or Vinyon filler fabric; a 30-cm. funnel is advisable.
5. A part of the amine usually crystallizes during the filtra-t ion. It is dissolved by warming, after which water is added until t lie solution is just cloudy.
6. If the melting point is low, a second recrystallization is needed.-
34
ORGANIC SYNTHESES
3. Methods of Preparation
4,4'-Diaminodiphenylsulfone and/or 4,4'-diacetylaminodi-phenylsulfone have been prepared by various procedures, starting with 4,4'-dinitrodiphenylsulfide;1 or 4,4'-dichlorodiphenylsul-fone.2, 3 It has also been made from a sulfmate and a halonitro-benzene; 4 from 4-acetylaminobenzenesulfonyl chloride and acet-anilide; 5 from acetanilide and thionyl chloride;6 from 4-nitro-4'-aminodiphenylsulfide;7 and by acetylation of thioaniline (4,4'-diaminodiphenylsulfide) followed by hydrogen peroxide oxidation.8 The 4,4'-diacetylaminodiphenylsulfone obtained by / of these procedures is readily deacetylated.7, 8 A method somewhat similar to the one described above has recently been patented.9
1 Fromm and Wittmann, Ber. 41, 2270 (1908).
21. G. Farbenind. A-G., Brit. pat. 506,227 [C. A. 33, 9328 (1939)].
31. G. Farbenind. A-G., Fr. pat. 829,926 [C. A. 33, 1760 (1939)].
4 Schering A-G., Brit. pat. 510,127 [C. A. 34, 4079 (1940)].
6 Kereszty and Wolf, Hung. pat. 120,021 [C. A. 33, 4600 (1939)].
6 Sugasawa and Sakurai, J. Pharm. Soc. Japan 60, 22 (1940) [C. A. 34, 3704 (1940)].
7 Raiziss, Clemence, Severac, and Moetsch, J. Am. Chem. Soc. 61, 2763 (1939).
8 Van Arendonk and Kleiderer, J. Am. Chem. Soc. 62, 3521 (1940).
9 Roblyn and Williams, U. S. pat. 2,227,400 [C. A. 35, 2531 (1941)].
2,6-DIMETHOXYBENZONITRILE
35
2,6-DIMETHOXYBENZONITRILE (Benzonitrile, 2,6-dimethoxy-)
O:
Nr^\NO:
4/
KCN
------->
CH3OH
CN
CH30f^\N02
KOH
*
CN
ch3o/\och3
Submitted by Alfred Russell and W. G. Tebbens.
Checked by R. L. Shbiner and Robert S. Voris.
1. Procedure
(A) 2-Nitro-6-methoxybenzonitrile.Five hundred grams (2.97 moles) of technical m-dinitrobenzene (m.p. 88-89) is dissolved in 7.5 1. of absolute methyl alcohol in a 12-1. round-bottomed flask fitted with an efficient mechanical stirrer. The temperature is raised to 40 by means of a water bath and maintained there while a solution of 230 g. of potassium cyanide in 400 cc. of water is added with stirring. The dark purple mixture is stirred for two hours and then is allowed to stand at room temperature for two to three days. The black precipitate is collected with suction on a Buchner funnel, pressed as dry as possible, and then spread out in the air to dry. It weighs about 185-188 g.
The filtrate is diluted with 60 1. of cold water (Note 1) and allowed to stand overnight. The brown sludge is filtered with suction (Note 2) and pressed as dry as possible on the funnel. After drying, it weighs about 164 g. The combined precipitates are refluxed for thirty minutes each with successive 650-, 500-, and 500-cc. portions of chloroform. The chloroform extracts are filtered while hot, and. the bright red filtrates are combined and concentrated to a volume of 500 cc. by distillation. One liter of petroleum ether (b.p. 60-90) is added, whereupon the crude
2-nitro-6-methoxybenzonitrile separates as a red powder. It is removed by filtration and air-dried. It weighs 120-125 g. (22 23 per cent of the theoretical amount) and melts at 148-157 (Note 3). It is used without purification (Note 4).
36
ORGANIC SYNTHESES
() 2,6-Dimethoxybenzonitrile.The crude nitrile is placed in a 3-1. flask and is refluxed for two hours with a solution of 75 g. of potassium hydroxide in 1.9 1. of methyl alcohol. The solution is concentrated by distillation to a volume of 400 cc. and then is poured into 4 1. of cold water. The brownish solid is filtered, washed thoroughly with cold water, and dried. The crude product (85-95 g.) is dissolved in 300 cc. of chloroform and refluxed with 8 g. of Darco for thirty minutes. The hot mixture is filtered, and 500 cc. of hot petroleum ether (b.p. 60-90) is added to the filtrate. The solution is cooled, and the light-tan-colored needles of 2,6-di-methoxybenzonitrile are removed'by filtration. The product weighs 75-86 g. (15-17 per cent of the theoretical amount) and melts at 116-117 (Note 5).
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