Abstract 7-Chloro-2-chloromethyl-benzofuran (13) and 3, 8-dichloro-2 H-1-benzopyran (12) are the main products from the thermal rearrangement (230–260) of 2, 6-dichlorophenyl propargyl ether (7). Compounds 17, 18 and 19 are also formed, but in much smaller amounts (scheme 2 and table 1). However, in the case of the bromo-compounds 8 and 9 the rearrangement products are the benzofuran derivatives 21 and 22, containing one ...