2-Alkyl-7-methoxy-5-nitrobenzo [b] furan, 2-alkyl-9-methoxy-7-nitro-3-oxo-2, 3-dihydro-5H- benzo [e][1, 4]-dioxepin-5-yl acetate and 2-alkyl-5-hydroxy-9-methoxy-7-nitro-5H-benzo [e][1, 4]-dioxepin-3-one were formed as a result of the cyclization of 2-(2-formyl-6-methoxy-4- nitrophenoxy) alkanoic acids under classical Perkin reaction conditions. The products were characterized by spectroscopic methods and the mechanism of the cyclization is ...