Eric Tan
ICIQ, SPain
Chelation-Assisted Metal-catalyzed Alkynylation of C(sp2)-H Bonds
The aryl-alkyne bond is widely present in natural products, drugs, or organic materials and the alkynyl-substituent often imparts interesting properties.1 The Sonogashira reaction is the most widely used method to construct the aryl-alkyne bond. However, in recent years, a complementary strategy emerged based on transition metals catalysts which are able, upon coordination to a directing group, to cleave C(sp2)-H bonds and forge aryl-alkyne bonds (Scheme 1).2 Typical directing groups are amide functional groups, which need to be installed and then removed, thus lowering the step- and atom-economy when used in synthesis. Our work aims to expand the scope of C-H alkynylation of (hetero)arenes, by developing reactions using instead widely used functional groups as directing groups, such as phenolic –OH, carboxylic acid, ester and ketone.
References
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