Expeditious synthesis of dihydrobenzo-[2,1-b:3,4-b′]-,[1,2-b:5,4-b′], and [1,2-b : 4,5-b′]-dipyrroles
Abstract
A simple, high-yield, two-step synthesis of the title compounds (1)–(3) is described, based on the catalytic reduction of the bis-enamines (4)–(6), in turn obtained by condensation of dimethylformamide diethyl acetal with the appropriate dinitro-xylene.