Reactions of Sulfonylphthalide with Diverse Activated Imines for the Synthesis of Enaminophthalides, <i>Spiro</i>-isoquinolinones, and Homalicine Natural Products
作者:Pallabita Basu、Nishikant Satam、Soumyaranjan Pati、Alati Suresh、Irishi N. N. Namboothiri
DOI:10.1021/acs.joc.2c00816
日期:——
various activated imines under basic conditions is demonstrated. The reaction of 3-sulfonylphthalide with Boc-protected aldimine provides a rapid access to 1,2-imine adducts and alkylidenephthalides depending upon the stoichiometry of the base. The alkylidenephthalides could be transformed to ketophthalides, a new class of phthalides, on acid hydrolysis, which upon reductive cyclization using Zn/AcOH
证明了 Hauser–Kraus (H–K) 供体 3-磺酰苯酞在碱性条件下与各种活化亚胺的反应性。根据碱的化学计量,3-磺酰苯酞与 Boc 保护的醛亚胺反应可快速获得 1,2-亚胺加合物和亚烷基苯酞。亚烷基苯酞可以在酸水解时转化为酮苯酞,一类新的苯酞,在使用 Zn/AcOH 进行还原环化后得到天然产物 homalicine。相反,Boc 保护的靛蓝亚胺经历有效的 H-K 环化以提供螺旋- 异喹啉酮 - 羟吲哚,收率极佳。然而,相应的共轭酮亚胺提供迈克尔加合物,其在 TBAF 条件下转化为相应的亚烷基苯酞。