Picric Chloride, and Alcohols. 349 



The /3-isomer (169°) is prepared in the same way as the 

 ethoxy-body, using methyl alcohol instead of ethyl alcohol. 



2*5 gm. picric chloride and '8 gm. NH 4 SCN were dissolved 

 separately in methyl alcohol, and then mixed while hot. Separa- 

 tion of an oil and a crumbling precipitate almost immediately 

 took place. This was filtered and washed with water, alcohol and 

 ether. The mother-liquor was found to be acid in this case also. 

 The product on crystallisation from glacial acetic acid or acetic 

 acid diluted with methyl alcohol, appeared as a light-yellow mass, 

 m.p. 169°. It was difficultly soluble in alcohol or ether, easily 

 soluble in glacial acetic acid. 



The a-isomer which was investigated first, is obtained from 

 the /3-isomer. 



5 gm. of the /3-isomer (169°) were crystallised from 140 c.c. of 

 ethyl alcohol and acetic acid (1 : 1), and the crystallisation care- 

 fully watched. 



After six hours the product was filtered off rapidly and washed 

 with alcohol and ether. The yield was 1*2 gm. of the a-isomer 

 (157 — 8°). The mother-liquor deposited the /3-isomer. The 

 a-isomer could not be further purified by crystallisation since it 

 was partially retransformed to the /3-isomer. It could be entirely 

 converted to the /3-isomer by simple crystallisation from methyl 

 alcohol and glacial acetic (1 : 1). 



The ease with which these bodies can be transformed one to 

 the other, suggests stereo-isomerism, and this can be easily ex- 

 plained on the Hartzsch-Werner theory of the trivalent nitrogen 

 atom. The forms would then correspond to the "syn" and "anti" 

 configurations. 



Pi-S-Kr 77-O-Et Pi-S-K- 7-O-Et 



and 



-Pi Pi 



Which structure to assign to each isomer has not yet been 

 determined, and further experiments are in progress to elucidate 

 these points. 



These compounds are also of interest, since they afford means 

 of obtaining well-crystallised derivatives of the alcohols, which may 

 serve for their characterisation and identification. 



