OPTICALLY ACTIVE TRIORGANOSILYL ESTERS OF PHOSPHORUS. SYNTHESIS AND STRUCTURE

Article abstract of DOI:10.1016/S0040-4020(01)87438-X

We report this synthesis of the first optically active silyl esters of phosphorus having two centres of chirality : one on silicon and the other on phosphorus.Compounds are obtained of general formula : t-BuPhP(X)YSiαNpPhMe X,Y=O, O(1); S, O(2); Se, O(3); S, S(4); doublet, O(5) including 1 and 3 with optical activity located on Si, 2 and 5 with the activity on Si or P and on both these centres, 4 only racemic.Absolute configurations are determined. 31P and 29Si NMR spectra of these models and their trimethylsilyl analogues are reported.The triorganosilyl group is always preferentially bound to phosphorus through oxygen atom.Surprisingly, diastereotopic NMR chemical shifts exclude the fast 1,3 migration in esters 1 and 4. 29Si NMR spectra correspond to a tetracoordinate silicon atom.