Generation of chiral phosphonium dialkyl phosphite as a highly reactive p-nucleophile: application to asymmetric hydrophosphonylation of aldehydes

The generation of chiral tetraaminophosphonium dialkyl phosphite is detected by low-temperature NMR analysis and its synthetic potential as a reactive P-nucleophile is shown by its application to the establishment of highly efficient and enantioselective hydrophosphonylation of various aldehydes. The analysis of the organic-base-dependent generation of the ion pair and its reactivity and selectivity as a P-nucleophile has shown that the structure of the cationic conjugate acid of the base is a major factor for generation of phosphite anions with nucleophilicity and rigorous stereocontrol.