|
[摘要]:A variety of oxazole derivatives that possess an alpha,beta-unsaturated substituent at the 2-position were conveniently synthesized in good yields via a Hantzsch-type reaction between dehydroamino acid amides and P-bromopyruvate derivatives. Furthermore, oxazoles with substituents at the 2- and 5-positions were also obtained in good yields using the corresponding beta-substituted beta-bromopyruvate derivatives. A revised reaction mechanism to explain the enhanced reactivity of dehydroamino acid amides for the Hantzsch-oxazole-type reaction is presented. |
|