A practical synthetic route to functionalized THBCs and oxygenated analogues via intramolecular Friedel–Crafts reactions
作者:Marco Angeli、Marco Bandini、Andrea Garelli、Fabio Piccinelli、Simona Tommasi、Achille Umani-Ronchi
DOI:10.1039/b607864h
日期:——
via InBr3-catalyzed intramolecular Friedel-Crafts (F-C) cyclization is described. The use of cross-metathesis reaction represents a direct route to the cyclization precursors and the use of InBr3 (5 mol%) allowed polycyclic indole compounds to be isolated in high yields under mild reaction conditions (rt, DCM, minutes). Finally, efforts toward the development of a stereocontrolled version of the present
一种实用的催化方法,用于合成4-取代的1,2,3,4-四氢-β-咔啉(THBCs,1)和1,2,3,9-四氢吡喃并[3,4-b]吲哚(2)描述了通过InBr 3催化的分子内Friedel-Crafts(FC)环化。交叉复分解反应的使用代表了通往环化前体的直接途径,InBr3(5摩尔%)的使用使得在温和的反应条件下(rt,DCM,分钟)可以高产率地分离出多环吲哚化合物。最后,提出了开发本环化的立体控制形式的努力,强调了[salenAlCl]和双金属[(salenAlCl)2 -InBr 3]体系是有前途的手性路易斯酸(ee高达60%)。