238 THE PREPARATION OF 



This reaction forms indeed the basis of a method for the 

 preparation of thionyl chloride, for if a current of chlorine 

 be passed into the mixture the liberated sulphur is recon- 

 verted into sulphur chloride, which then reacts with a further 

 quantity of trioxide (D. R. P. 139455; Abstr., 1902, ii. 420). 



The behaviour of sulphur chloride towards hydrocarbons 

 and phenols may be noticed. Boeseken (Eec. Trav. Chim., 

 1905, 24, 209) found that benzene and sulphur chloride react 

 together in presence of aluminium chloride, so that diphenyl 

 sulphide and free sulphur are formed quantitatively according 

 to the equation : 



2C 6 H 6 +S 2 C1 2 = (C 6 H 5 ) 2 S+S+2HC1, 



while Cohen and Skirrow (Trans., 1899, 75, 887) obtained 

 diphenylene disulphide 



C 6 H 4 < >C 6 H 4 



and free sulphur from the same substances when aluminium 

 chloride was employed as catalyst. 



The reaction between phenol and sulphur chloride is 

 vigorous, and among the products are dihydroxy-diphenyl 

 sulphide S(C 6 H 4 OH) 2 , free sulphur, and probably a disulphide 

 S 2 (C 6 H 4 OH) 2 . Somewhat similar products were obtained by 

 Henriquez (Ber., 1894, 27, 2992) from sulphur chloride and 

 naphthol. 



If we accept the unsymmetrical formula S : SC1 2 we can 

 readily understand that the divalent sulphur atom may 

 easily be split off in all the above cases with formation of a 

 monosulphide : 



R 2 S : S ^ R 2 S+S, 



while with the symmetrical formula Cl. S. S. Cl the formation 

 of a monosulphide is less intelligible. 



The salt-like metallic derivatives of imides react with 

 sulphur chloride though less readily than ordinary metallic 



