Steroids and Walden inversion. Part LXV. Comparative experiments on the deamination of cis- and trans-4-t-butylcyclohexylamine

Abstract

Deamination of trans-4-t-butylcyclohexylamine (NH₂eq) in 50% acetic acid at 20° gives alcohols (63%) with 93% retention, and acetates (35%) with 73% retention; in acetic acid at 20° alcohols (42%) are formed with 95% retention, and acetates (52%) are formed with 78% retention. Very little elimination (2%, 6%) occurs. Deamination of cis-4-t-butylcyclohexylamine (NH₂ax) in 50% acetic acid at 20° gives alcohols (35%) with only 54% retention, and acetates (18%) with only 41% retenion; in acetic acid at 20° alcohols (19%) are produced with 78% retention, whilst acetates (31%) are produced with only 44% retention. Considerable elimination (47% 50%) occurs.

These results provide further evidence that the deamination is a complex reaction, greatly influenced by steric environment, and proceeding by a combination of S_Ni, S_N2, and E2 mechanisms and mechanisms involving an intermediate solvated carbonium ion.