1, 3-Oxazines and related compounds. XIII. Reaction of acyl Meldrum's acids with Schiff bases giving 2, 3-disubstituted 5-acyl-3, 4, 5, 6-tetrahydro-2H-1, 3-oxazine-4, 6 …

Y YAMAMOTO, Y WATANABE, S OHNISHI

Index: Yamamoto, Yutaka; Watanabe, Yukiyoshi,; Ohnishi, Shuhei Chemical & Pharmaceutical Bulletin, 1987 , vol. 35, # 5 p. 1860 - 1870

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Citation Number: 40

Abstract

The reactions of Schiff bases (2) with various acyl Meldrum's acids (1) were investigated. Refluxing of 1 and 2 in benzene caused an exchange reaction of the acetone moiety of 1 with the Schiff base moiety through the intermediate acylketenes 11 formed in situ from 1 to give 2, 3-disubstituted 5-acy1-3, 4, 5, 6-tetrahydro-2H-1, 3-oxazine-4, 6-diones (3). The oxazindiones 3 underwent thermal conversion to afford 2, 3, 6-trisubstituted 2, 3-dihydro-1 ...