REACTION OF DIALKOXYTHIOXAPHOSPHORANESULFENYL CHLORIDES WITH DIALKYL TRIMETHYLSILYL PHOSPHITES. NEW STEREOSELECTIVE ROUTE TO THE UNSYMMETRICAL TETRAALKYL DITHIOPYROPHOSPHATES. PREPARATION OF DIASTEREOISOMERIC 2-TRIMETHYLSILYLOXY-4-METHYL-1,3,2-DIOXAPHOSPHORINANES

Abstract
Unsymmetrical dithiopyrophosphates (RO)2P(S)SP(O)(RO)2 5 are formed in excellent yield and purity in reaction of dialkoxythioxaphosphoranesulfenyl chlorides 1 with trimethylsilylphosphites Me3SiOP(OR′)2 4. The full stereospecificity of this reaction has been demonstrated with an aid of diastereoisomeric cis- and trans-2-trimethylsilyloxy-4-methyl-1,3,2-dioxaphosphorinanes 9 which react with 1 with full retention of configuration at the phosphorus center. Preparation of diastereoisomeric cis- and trans-9 has been described and their configuration established.