Novel Diels–Alder Reaction of 4-Nitro-1(2H)-isoquinolones

Abstract

A novel Diels–Alder (DA) reaction with 4-nitro-1(2H)-isoquinolones acting as the dienophile afforded 5(6H)-phenanthridone derivatives. The DA reaction of 4-nitro-1(2H)-isoquinolone with 1-methoxy-1,3-butadiene gave biologically active 5(6H)-phenanthridone possessing in a high yield. Regioselectivity of 4-nitro-1(2H)-isoquinolones with 1-methoxy-3-silyloxy-1,3-butadiene was calculated using molecular orbital (MO) calculations.