A controlled regioselective synthesis of either C-2 or C-3 substituted benzo [b] furans from readily accessible 1-(2-hydroxyphenyl)-2-chloroethanones is described. Addition of a range of Grignard reagents to the α-chloro ketones generates alkoxide intermediates, which can form either 2-substituted benzo [b] furans via a [1, 2]-aryl migration or 3-substituted benzo [b] furans via a direct cyclization and dehydration sequence. A temperature-dependent [1, 2]- ...