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Updated: Sep 28, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Catalytic hunsdiecker reaction of alpha,beta-unsaturated carboxylic acids: how efficient is the catalyst?
1Organometallics & Catalysis Laboratory, Chemistry Department, Indian Institute of Technology, Kharagpur 721302, India.
Abstract:
UV-vis spectrophotometry is utilized to measure the relative efficiency of lithium acetate, tetrabutylammonium trifluoroacetate, and triethylamine as catalysts for the conversion of 4-methoxycinnamic acid to 4-methoxy-beta-bromostyrene. In acetonitrile-water as solvent, the efficiency order is lithium acetate > triethylamine > tetrabutylammonium trifluoroacetate. For triethylamine as catalyst, solvent-dependent order is acetonitrile-water > dichloromethane > acetonitrile. Using triethylamine as catalyst (5-20 mol %), cinnamic acids, and propiolic acids are converted to corresponding beta-bromostyrenes and 1-halo-1-alkynes in 60-98% isolated yields within 1-5 min.
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