Scalable and Straightforward Synthesis of a 2-Alkyl-7-Arylbenzo­thiophene as a GPR52 Agonist via a Hemithioindigo Derivative

Abstract

A simple and efficient procedure has been developed for the synthesis of the GPR52 agonist N-(2-amino-2-oxoethyl)-3-{4-fluoro-2-[3-(trifluoromethyl)benzyl]-1-benzothien-7-yl}benzamide. The benzo­thiophene unit was directly constructed by reduction of a hemithioindigo derivative prepared by an intramolecular Friedel–Crafts cyclization of (phenylsulfanyl)acetic acid, followed by dehydrative benzylidene formation.

Key words

benzothiophenes - Friedel–Crafts reactions - cyclizations - scalable syntheses - medicinal chemistry

• References

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