ChemInform Abstract: Menthyl‐Substituted Organophosphorus Compounds. Part 6. Preparation of P(L‐men)RCl and P(L‐men)R(S)Cl (R: Me, Et, iPr, tBu, or Ph; men: cyclo‐C6H9‐2‐iPr‐5‐Me) and NMR Studies of Configuration and Halogen Exchange.

Abstract

237ChemInform Abstract The menthyl-substituted chlorophosphines (I) are prepared by reaction of PRCl2 (R: Ph, Me, Et) with Mg(L-men)Cl or P(L-men)Cl2 with MgRCl (R: iPr, tBu) and are converted into the epimeric thiophosphoryl chlorides (II) and (III). These series are subjected to 1H, 13C, and 31P NMR studies at ambient temperature. Chemical shifts of C-4, C-8, H-8, CH3-7, CH3-9, and CH3-10 and the coupling constants 2JPC-2, 2JPC-4, 3JPC-1, and 3JPC-8 are stereospecific indicators for the configurations of phosphorus in P-epimeric forms (II) and (III). Influences from substituents R on chemical shifts and coupling constants are discussed. Variable-temp. 31P NMR studies using line broadening and selective inversion-recovery techniques on chlorophosphines (I) (R: Ph, Et) reveal halogen-exchange processes which arelikely to have cationic phosphorus intermediates.