Substrate-Controlled Regioselective Alkylation of 4-Hydroxycoumarin with Diazo Compounds through TfOH Catalysis

Abstract

Control of the regioselectivity of nucleophiles toward alkylating agents is a fundamental problem in heterocyclic chemistry. Substrate-controlled TfOH-catalyzed alkylation of 4-hydroxycoumarin with diazo compounds has been developed to provide rapid access to the C3- or O-alkylated 4-hydroxycoumarins with high efficiency. The regioselectivity can be determined by varying the electronic nature of the diazo substrates, especially those bearing a methylthio group.

Key words

4-hydroxycoumarin - diazo compounds - metal-free catalysis - alkylation - regioselectivity

Publication History

Received: 06 October 2023

Accepted after revision: 07 November 2023

Article published online:
06 December 2023

• References and Notes

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