Attrition‐Enhanced Deracemization of Axially Chiral Nicotinamides

Abstract

Attrition‐enhanced deracemization of two axially chiral nicotinamides, crystallizing as a conglomerate of a P 2 1 crystal system, was performed. N , N ‐Dialkylnicotinamides with substituents on the 2‐ and 4‐positions of the pyridine ring exhibited stable axial chirality due to rotationally restricted scaffolds for the Ar–C(=O)N bond. Crystallization of the racemic mixtures from the melt or attrition‐enhanced deracemization led to the chiral breaking of symmetry to give 95–96 % ee of enantiomorphic crystals.