A general synthetic method of 4-substituted indoles was examined.The Fischer indolization of phenylhydrazones (2, 3, 7, and 8) having chlorine on & position gave 7-chloro-4-substituted indoles (4, 9, and lo), which were converted to 4-substituted indoles (5 and 13) by catalytic hydrogenation.Cyclization of 3-(2-ethoxy~arbonyl-7-chloroindol-4-yl)propionic acid (10) with polyphosphoric acid (PPA)...