ChemInform Abstract: Solvent‐Free Friedel—Crafts Cyclization with Trichloroacetic Anhydride.

Abstract

Ring closure reactions O 0130Solvent-Free Friedel-Crafts Cyclization with Trichloroacetic Anhydride. -The scope of the title reaction is explored with the synthesis of tetralones (II), benzothiopyrans (IV), benzoxepins and benzothiepines (VIII) as well as dibenzoxepins and dibenzothiepins (VI). Phenoxy-or phenylthiopropanoic acids do not react to the corresponding benzofuran or benzothiophene derivatives and the formation of eight-membered heterocycles such as (VIIIc) also fails. -(ANDREWS, B.; BULLOCK, K.; CONDON, S.; CORONA, J.; DAVIS*, R.; GRIMES, J.; HAZELWOOD, A.; TABET, E.; Synth. Commun. 39 (2009) 15, 2664-2673; Chem. Dev., GlaxoSmithKline, Research Triangle Park, NC 27709, USA; Eng.) -H. Haber 51-039