Tetrahedron letters

Fluorine as an ortho-directing group in aromatic metalation: a two step preparation of substituted benzo [b] thiophene-2-carboxylates

AJ Bridges, A Lee, EC Maduakor, CE Schwartz

Index: Bridges, Alexander J.; Lee, Arthur; Maduakor, Emmanuel C.; Eric Schwartz Tetrahedron Letters, 1992 , vol. 33, # 49 p. 7499 - 7502

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Citation Number: 74

Abstract

Abstract A simple 2-step synthesis of B-ring substituted benzo [b] thiophene-2-carboxylates from aryl fluorides has been developed. The route involves a selective lithiation ortho to fluorine, followed by formylation, and subsequently, displacement of fluorine with thioglycollate and base-induced ring closure in a single operation.