N-Formylenamides of isoquinoline (6) were obtained from N-[2-(2-acyl-4,5 -dimethoxyphenyl)ethyl] formamides (5) by cyclization in the presence of catalytic amount of p-toluensulfonic acid. The starting keto formamides (5) were obtained by acylation of a N-[2-(3,4-dimethoxyphenyl)ethyl] formam ides (1) with carboxylic acids or their anhydrides in polyphosphoric acid (PPA).
N-Formylenamides of isoquinoline (6) were obtained from N-[2-(2-acyl-4,5 -dimethoxyphenyl)ethyl] formamides (5) by cyclization in the presence of catalytic amount of p-toluensulfonic acid. The starting keto formamides (5) were obtained by acylation of a N-[2-(3,4-dimethoxyphenyl)ethyl] formam ides (1) with carboxylic acids or their anhydrides in polyphosphoric acid (PPA).
N-Formylenamides of isoquinoline (6) were obtained from N-[2-(2-acyl-4,5 -dimethoxyphenyl)ethyl] formamides (5) by cyclization in the presence of catalytic amount of p-toluensulfonic acid. The starting keto formamides (5) were obtained by acylation of a N-[2-(3,4-dimethoxyphenyl)ethyl] formam ides (1) with carboxylic acids or their anhydrides in polyphosphoric acid (PPA).