Concise Synthesis of 6-Cyanobenzo[b]furan, a Useful Building Block

Abstract

A new three-step synthesis of 6-cyanobenzo[b]furan (6) was developed, starting from commercially available 6-hydroxybenzo[b]furan-3-one (18). Key steps in this process were the first step, which was the reductive dehydration of 18 to produce 6-hydroxybenzo[b]furan (19), and the last step, which converted the aryl triflate 20 to the aryl cyanide 6 in a palladium-catalyzed cross-coupling protocol. Overall yield for this new synthesis was 49%.

GRAPHICAL ABSTRACT

Keywords:

• 6-Cyanobenzo[b]furan
• aryl cyanide synthesis
• cross-coupling
• reductive dehydration

Notes

^a Isolated yields.