Synthesis and thermal stability of S-trimethylsilyl esters of tetracoordinated phosphorus amidothioacids

Abstract

S-(Diethylamino)dimethylsilyl bis(diethylamido)dithiophosphate 3 was obtained by the reaction of tetraphosphorus decasulfide 1 with bis(diethylamino)dimethylsilane 2a. The reactions of Lawesson's reagent 5 with 2a and the alkyl homologues of Davy's reagent 8a,b with trimethyl(diethylamino) silane 6 were studied. On the basis of these reactions, methods of synthesizing S-(diethylamino)dimethylsilyl or S-(diethylamino)-diphenylsilyl 4-methoxyphenyl (diethylamido)dithiophosphonates 7a and 7b and S-trimethylsilyl S-alkyl(diethylamido)tnthiophosphates 9a,b are described. The optimal reaction conditions and thermal stability of S-trimethylsilyl S-ethyl(diethylamido) trithiophosphate 9a were defined by differential thermal analyses. Compound 9a have been decomposed to form 2,4-bis(diethylamido)-1,3,2,4-dithiadiphosphetane- 2,4-disulfide 10 which structure was established by X-ray single crystal diffraction. © 2006 Wiley Periodicals, Inc.