Convenient Synthesis of Tolcapone, a Selective Catechol‐O‐methyltransferase Inhibitor

Abstract

A convenient and efficient synthesis of tolcapone from commercial 4‐benzyloxy‐3‐methoxybenzaldehyde is presented. Grignard reaction of 4‐benzyloxy‐3‐methoxybenzaldehyde (1) with p‐tolylmagnesium bromide followed by Oppenauer oxidation of the hydroxyl functionality and subsequent O‐debenzylation gave phenol 5. Compound 5 was regioselectively nitrated and then subjected to O‐demethylation to produce tolcapone in 60% overall yield.

Keywords:

• catechol‐O‐methyltransferase
• nitration
• tolcapone

Acknowledgment

This work was supported by the National Institute of Mental Health under Contract N01‐MH‐32005.