A simple, high-yielding synthesis of 2-vinyl-3H-quinazolin-4-one, 2-(1-chlo
rovinyl)-3H-quinazolin-4-one and 2-(1-bromovinyl)-3H-quinazolin-4-one. The
2-vinylquinazolinones 11a and 14 participate readily in nucleophilic additi
on reactions. Treatment with both carbon and nitrogen nucleophiles results
in a clean conversion into a variety of 2-substituted 3H-quinazolin-4-one d
erivatives. The 2-(1-halovinyl)-3H-quinazolin-4-ones 11b and Ile reacted wi
th carbon nucleophiles to give several derivatives of 2-substituted 3H-quin
azolin-4-one, such as dihydrofurancarboxylic ethyl ester 23. (C) 2000 Elsev
ier Science Ltd. All rights reserved.