Reaction of Isoquinoline Enamides with Electrophiles

Article abstract of DOI:10.1021/jo00137a004

The reaction of isoquinoline enamides with acyl isocyanates yields vinylogous amides through carbon-carbon bond formation between the β carbon of the enamide and the isocyanate carbonyl.Enamide formation occurs between 1-benzyl-3,4-dihydroisoquinolines and phenylacetic anhydride.However, a N,C-bis(phenylacetyl) derivative is formed with phenylacetyl chloride.The reaction occurs through preferential reaction of phenylketene with the enamine tautomer of the 1-benzyl-3,4-dihydroisoquinoline at the carbon terminus, followed by N-acylation.The equilibrium is demonstrated by deuterium NMR.