A New Route to 1,3-Disubstituted Benzothiophenes

Article abstract of DOI:10.1021/jo00021a012

A facile synthesis of 1,3-dichlorobenzothiophene 3 is described.Lithium-chlorine exchange of 3, followed by reaction with various electrophiles, provides a route to 1-acyl-3-chlorobenzothiophenes, as well as to the very stable 1,3-bis(tert-butyldimethylsilyl)benzothiophene (9).Compound 9 unddergoes silyl replacement reactions with acylating agents, as well as an unusuak oxidative desilylation by I2 or TiCl4, to give the capped disilylated dimer, trimer, and tetramer (16,17, and 18) of benzothiophene.