E–Z-isomerism in aldimines
Abstract
A range of ortho-disubstituted C-aryl aldimines has been synthesized. N.m.r. spectroscopic analysis revealed a significant proportion of the Z-isomer at equilibrium in solution. The E–Z-isomer distribution is critically examined in terms of electronic, steric, and solvent effects. The effect of trace amounts of carboxylic acid on imine stereomutation is discussed.