Direct transacylation of 2,2,2-trihaloethyl esters with amines and alcohols using phosphorus (III) reagents for reductive fragmentation and in situ activation.
Direct transacylation of 2,2,2-trihaloethyl esters with amines and alcohols using phosphorus (III) reagents for reductive fragmentation and in situ activation.
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DOI：
10.1021/jo991711m
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发表时间：
2000-04
期刊：
影响因子：
--
通讯作者：
J. Hans;R. Driver;S. D. Burke
中科院分区：
文献类型：
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作者：
J. Hans;R. Driver;S. D. Burke
酰胺和酯已被合成从2，2，2-三卤代乙酯在一锅中使用磷-（III）试剂作为还原剂，与所得的羧酸活化作为酰氧基磷中间体，和原位捕获胺或醇亲核试剂。使用六甲基磷酰三胺（Me 2N）3 P作为还原剂，以良好的产率合成了仲酰胺和叔酰胺，包括二肽。使用三丁基膦和DMAP，获得了由伯醇和仲醇衍生的酯的最佳产率。三溴乙酯的产率比三氯乙酯的产率高上级。
Amides and esters have been synthesized from 2,2,2-trihaloethyl esters in one pot using phosphorus-(III) reagents as reductants, with resultant carboxylate activation as an acyloxyphosphonium intermediate, and in situ trapping by amine or alcohol nucleophiles. Secondary and tertiary amides were synthesized, including a dipeptide, in good yields using hexamethylphosphorous triamide (Me2N)3P, as reducing agent. Optimal yields of esters derived from primary and secondary alcohols were obtained using tributylphosphine and DMAP. Tribromoethyl esters provided yields superior to those obtained with trichloroethyl esters.