Expeditious Microwave-Assisted Synthesis of 5-Alkoxyoxazoles from α-Triflyloxy Esters and Nitriles
作者:Laurie-Anne Jouanno、Cyrille Sabot、Pierre-Yves Renard
DOI:10.1021/jo301527t
日期:2012.10.5
A rapid and general access to diversely substituted 5-alkoxyoxazoles 2 (i.e., R1, R2 = alkyl, phenyl) from easily accessible α-triflyloxy/hydroxy esters 1 and nitriles with good yields (41–76%) is reported. The versatility of the cyclization is shown for a range of substrates with high selectivity toward triflates over mesylates and proved to be compatible with sensitive functional groups. As an illustration
据报道,从易于获得的α-三氟乙氧基/羟基酯1和腈中,可以快速,普遍地获得各种取代的5-烷氧基恶唑2(即R 1,R 2 =烷基,苯基),产率高(41-76%)。示出了环化的多功能性,其对于一系列对甲磺酸酯上的三氟甲磺酸酯具有高选择性的底物,并证明与敏感的官能团相容。为了说明这种转变,最近分离出的羟基吡啶甲基多juguinate 4的第一个合成过程是通过5-烷氧基恶唑和丙烯酸的杂Diels-Alder反应,然后进行原脱羧反应,分四个步骤完成的。