Enzymatic kinetic resolution in the synthesis of new precursors of P-chiral organophosphorus catalysts: phosphines and their P-boranes

The CAL-B-mediated kinetic resolution of racemic 2-hydroxymethylphenyl-(methyl)phenylphosphine and its P-BH3 analogue gave, via their enantioselective monoacetylation, the corresponding monoacetates and unreacted substrates in moderate yields and with indeterminate enantiomeric excess, depending on the solvent applied. The P-BH3 analogues were transformed into 2-aminomethyl derivatives via O-tosyl or O-mesyl intermediates, which will be checked as tridentate catalyst/ligands in asymmetric synthesis.