SN2 displacement at the quaternary carbon center: a novel entry to the synthesis of α,α-disubstituted α-amino acids

A novel method for the S(N)2 reaction on quaternary carbon atoms using bis(p-nitrophenyl)phosphorazidate has been developed. Chiral tertiary alcohols were directly converted into the corresponding chiral tertiary azides with complete inversion of configuration. Several alpha,alpha-disubstituted alpha-amino esters or amino acids were prepared through the conversion of azides to the corresponding amines by catalytic hydrogenation. (C) 2015 Elsevier Ltd. All rights reserved.