Cyclic sulfamidates as versatile lactam precursors. An evaluation of synthetic strategies towards (−)-aphanorphine
作者:John F. Bower、Peter Szeto、Timothy Gallagher
DOI:10.1039/b614999e
日期:——
led to the efficient asymmetric synthesis of (-)-aphanorphine is reported. Two routes to the key cyclic sulfamidate intermediate are described, the first was based on a chiral auxiliary approach and the second utilised asymmetric hydrogenation methodology. A range of C(3)-substituted lactams (, and ) were synthesised and evaluated as precursors for Pd(0) catalysed entries (based on (i) alpha-arylation
报道了导致有效高效不对称合成(-)-Aphanorphine的全部研究。描述了两种通往关键环状氨基磺酸酯中间体的途径,第一种基于手性辅助方法,第二种采用不对称氢化方法。合成了一系列C(3)取代的内酰胺(和),并将其评估为Pd(0)催化条目的前体(基于(i)内酰胺烯醇的α-芳基化和(ii)还原性Heck反应)。 3-苯并ze庚因核心。这些方法不如芳基自由基环化有效,后者允许由茴香醛完成12个步骤的合成。