Dioxopyrrolines. Part LVIII. Rearrangement of 2,3-Dioxo-1,4-oxazines to 4,5-Dioxooxazoles in the Reaction with Dimethylsulfoxonium Methylide.
作者:Jun TODA、Masaharu SEKI、Kazuko AMANO、Taichi OYAMA、Takehiro SANO、Fumiyuki KIUCHI、Yoshisuke TSUDA
DOI:10.1248/cpb.42.739
日期:——
Reaction of 2, 3-dioxo-2, 3-dihydro-4H-1, 4-oxazines 2a-e with dimethylsulfoxonium methylide introduced an exo-methylene group with concomitant ring contraction to give 4, 5-dioxo-2, 3, 4, 5-tetrahydrooxazoles 3a-e in moderate yields. Mechanism of this unusual reaction was discussed.
2, 3-二酮-2, 3-二氢-4H-1, 4-噁唑啉 2a-e 与二甲基亚磺酸钠甲基负离子的反应引入了一个外部亚甲基组,同时伴随环收缩,生成了4, 5-二酮-2, 3, 4, 5-四氢噁唑 3a-e,产率适中。讨论了这一非寻常反应的机制。