78 Mr Ruhemann, Studies on Unsaturated Ketonic Compounds. 



these substances from the former compounds which are produced 

 at the same time. 



Mercaptans combine with acetylenic ketones as readily as 

 with olefinic ketones. As yet I have examined in this direction 

 particularly methoxybenzoylphenylacetylene, 



C 6 H 5 .C:C.CO.C 6 H 4 .O.CH 3 , 



which unites with 1 mol. of phenylmercaptan to yield 



C 6 H 5 . C (S . C 6 H 5 ) : CH . CO . C 6 H 4 . . CH 3 (m.p. 121—122°). 



This compound differs from the additive products of mercaptans 

 with olefinic ketones inasmuch as it is yellow whilst the latter 

 substances are colourless. 



At present I am engaged in the study of the thiol-compounds ; 

 it is especially their behaviour towards heat which appears to be 

 worthy of an inquiry for the following reason. The saturated 

 /3-hydroxyacids, on heating, split off water and yield unsaturated 

 acids ; the additive products of the olefinic ketones : 



I 

 — C :CH.CO— 



with primary organic bases suffer a similar decomposition (see 

 "Ruhemann and Watson, Trans. Ghem. Soc. 1904, lxxxv. 1170) 

 which takes place either in the direction 



I. R . CH (NH . HO . CH 2 . CO— 



-^ R.CH:CH.CO— + NH 2 .R', 



or 



II. R.CH(NH.R').CH 2 .CO— 



— ^ R.CH: N.R' + CH 3 — CO— 



(R and R' denoting hydrocarbon radicles). 



On the other hand, the additive compounds of acetylenic 

 ketones with organic bases seem to distil without decomposition. 

 As yet I have examined in this direction the compound 



C 6 H 5 . C (NH . C 6 H 5 ) : CH . CO . C 6 H 5 , 



which E. R. Watson (Trans. Ghem. Soc. 1904, lxxxv. 1324) has 

 obtained from methoxybenzoylacetylene and aniline, and have 

 ascertained that, in a vacuum, it boils unchanged. If the additive 

 products of the unsaturated ketones with mercaptans behave in 

 a similar manner, then it may be expected that the substances 

 which are formed from olefinic ketones will suffer an analogous 

 decomposition, whilst the compounds which result from the union 

 of mercaptans with acetylenic ketones will boil without decom- 

 position. 



