A Facile and Divergent Synthesis of Substituted Pyridine-2,4(1H,3H)-diones and 4H-Thiopyran-4-ones from α-Alkenoyl-α-carbamoyl Ketene-S,S-acetals
作者:Jinying Liu、Xiaolan Fu、Yang Zhou、Guangyuan Zhou、Yongjiu Liang、Dewen Dong
DOI:10.1071/ch09489
日期:——
divergent synthesis of substituted pyridine-2,4(1H,3H)-diones and 4H-thiopyran-4-ones from readily available α-alkenoyl-α-carbamoyl ketene-S,S-acetals has been developed. Subjected to N,N-dimethylformamide at 125°C, α-alkenoyl-α-carbamoyl ketene-S,S-acetals underwent an intramolecular aza-nucleophilic vinyl substitution reaction, a formal [5C + 1N] annulation, to give the corresponding substituted pyridine-2
从容易获得的α-烯酰基-α-氨基甲酰基酮烯-S,S-乙缩醛中轻松开发了取代吡啶-2,4(1 H,3 H)-二酮和4 H-噻喃-4-酮的合成方法。在125°C下于N,N-二甲基甲酰胺下,对α-链烯酰基-α-氨基甲酰基酮基-S,S-缩醛进行分子内氮杂亲核乙烯基取代反应,进行正式的[5C + 1N]环化反应,得到相应的取代基吡啶-2,4(1 H,3 H)-二酮的高收率,而在Na 2 S·9H 2的存在下在75°C的DMF中,O发生串联的分子间和分子内硫-亲核乙烯基取代反应,发生正式的[5C + 1S]环化反应,以高收率产生了相应的取代4 H -thiopyran-4-ones。