Polycyclic N ‐Heterocyclic Compounds, Part 69: Synthesis of 5‐amino‐1,2‐dihydro[1]benzofuro[3,2‐ d ]furo[2,3‐ b ]pyridines and their transformations to related compounds

Reaction of 3‐(3‐cyanopropoxy)[1]benzofuran‐2‐carbonitriles with potassium tert ‐butoxide gave 5‐amino‐1,2‐dihydro[1]benzofuro[3,2‐ d ]furo[2,3‐ b ]pyridines and 5‐amino‐2,3‐dihydro[1]benzofuro[3,2‐ b ]oxepin‐4‐carbonitriles as new ring systems. Reactions of the 5‐chloro derivative, obtained from 5‐amino‐1,2‐dihydro[1]benzofuro[3,2‐ d ]furo[2,3‐ b ]pyridine, produced a dihydrofuran ring‐opened compound and 5‐substituted compounds. J. Heterocyclic Chem.,(2011).