Synthesis and Selective<i>N</i>,<i>O</i>-Functionalization of Pyrazolone-Fused 3-Aminoazepinones
作者:Ben Schurgers、Guy Van Lommen、Guido Verniest
DOI:10.1002/ejoc.201500122
日期:2015.6
A new class of pyrazolone-fused 3-amino-1,3,4,7-tetrahydro-2H-azepin-2-ones was synthesized from azepane-based α,β-unsaturated esters. The latter compounds were obtained efficiently from 2-Cbz-amino-N-(2-bromoallyl)-4-pentenamide derivatives through initial Pd-catalyzed methoxycarbonylation followed by ring-closing metathesis. These new 3-aminotetrahydroazepinone esters were condensed with hydrazine
从基于氮杂环庚烷的α,β-不饱和酯合成了一类新的吡唑啉酮稠合的3-氨基-1,3,4,7-四氢-2H-azepin-2-ones。后一种化合物是从 2-Cbz-氨基-N-(2-溴烯丙基)-4-戊烯酰胺衍生物通过初始 Pd 催化的甲氧基羰基化和闭环复分解有效获得的。这些新的 3-氨基四氢氮杂酮酯与肼缩合,并在温和条件下使用 CuCl2 进行氧化。所得的双环吡唑啉酮通过 O-三氟甲磺酸化和使用(双)亲电子试剂对吡唑啉酮核进行选择性 N-1- 和 O-烷基化,转化为有价值的药物化学结构单元。