Transamidation Reactions. Part 11) N-Substituted 3-Aminopropanenitriles and 2-Aminoacetonitriles as Schiff-Base Equivalents

Article abstract of DOI:10.1002/hlca.19850680325

In presence of a strong base, the 13-membered cyclic compound 3 yielded, by loss of acetonitrile or its equivalent, the bicyclic product 5 instead of the 17-membered compound 4 as expected (Scheme 2).Investigation of model compounds (Scheme 4) and of model reactions (Schemes 5 and 6) led to the conclusion that the reaction proceeds via an intermediate formaldehyde imine; a Schiff base, e. g. 3b (Scheme 5), which reacts intra- and intermolecularly with a nucleophile to form a Mannich-type product.It seems to be a general principle that N-substituted 3-aminopropanenitrile and 2-aminoacetonitrile derivatives behave in the presence of a strong base as Schiff-base equivalents (Scheme 5 and 6).