Intermediates in the photochemical reaction of tetraphosphorus trisulphide with organic disulphides; phosphorus-31 nuclear magnetic resonance parameters for 2,6-bis(alkylthio)- and 2,6-di-iodo-3,5,7-trithia-1,2,4,6- tetraphosphabicyclo[2.2.1]heptanes and for 3,6-bis(alkylthio)-2,5,7-trithia- 1,3,4,6-tetraphosphabicyclo[2.2.1] heptanes

Abstract

P₄S₃(1) reacts with organic disulphides RSSR under glass-filtered u.v. irradiation to give at first β-P₄S₃(SR)₂(2) and then α-P₄S₃(SR)₂(3)(R = Me, Et, or Ph), identified in the product mixtures by their ³¹P n.m.r. spectra. The identities of β-P₄S₃(SPh)₂ and α-P₄S₃(SR)₂(R = Et or Ph) have been confirmed by the preparation of products with the same spectra by substitution reactions of β-P₄S₃I₂ or α-P₄S₃I₂ respectively. The ³¹P n.m.r. spectrum of β- P₄S₃I₂is reported.