Abstract
A simple and convenient synthesis for functionalised bi-2(1H )-pyrazinones 9 , 11a -h starting from 3,5-dichloro-2(1H )-pyrazinones 7 , 10a -h is described. The pyrazinone is homo-coupled by means of a Suzuki-type reaction of an in situ generated boronate. The reactions were carried out under conventional heating as well as under microwave irradiation and dramatic improvements in the rates and yields have been observed under the latter conditions.
Key words
bis-heterocycle - pyrazinone - Suzuki chemistry - bis(pinacolato)diboron
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