Atropselective Synthesis of <i>N,C</i>-Bis(diphenylphosphanes) from Bridged 2-Arylindoles Based on Effective Point-to-Axial Asymmetric Inductions after an Unusual Dilithiation
作者:Felix Bäuerle、Reinhard Brückner
DOI:10.1021/acs.orglett.9b03896
日期:2019.12.20
anhydride and 6 ensuing steps gave veratrol-annulated dimethylcyclo-heptenone diastereomers with 99% ee; ring closures occurred by Friedel-Crafts acylations of carboxylic acids obtained by stereospecific hydrogenolyses of a pair of diastereomeric δ-lactones. The mentioned cycloheptenones and Ph-NH-NH2 underwent Fischer indole syntheses providing the tetracyclic indoles cis- and trans-14a, respectively. Double
戊二酸酐的不对称甲醇分解和随后的6个步骤得到了具有99%ee的藜芦醇环抱的二甲基环庚烯酮非对映异构体;闭环是由一对非对映体δ-内酯的立体定向氢解所获得的羧酸的Friedel-Crafts酰化作用而发生的。所提及的环庚烯酮和Ph-NH-NH 2进行费歇尔吲哚合成,分别提供四环吲哚顺式和反式-14a。用BuLi进行的两次锂化反应和用ClPPh2进行的淬灭反应分别使二膦顺式和反式15具有完美的(P)-和(M)-atropselective选择性。