AbstractThis work deals with the development of a new family of planar chiral phosphoric acids based on a ferrocenophane/paracyclophane scaffold. The synthetic approach has been improved by taking advantage of a chiral phosphorylating agent to access enantiomerically enriched acids via diastereomers separation. These phosphoric acids have been used as catalysts for the enantioselective H‐transfer reduction of α‐substituted quinolines with Hantzsch esters. Optimization of both the catalyst and the Hantzsch reductant allowed ee values in the range 82–92% to be attained starting from α‐arylquinolines.magnified image
ULDRIKIS YA. R.; DUBUR G. YA.; DIPAN I. V.; CHEKAVICHUS B. S., XIMIYA GETEROTSIKL. SOEDIN. <KGSS-AQ>, 1975, HO 9, 1230-1237
作者:ULDRIKIS YA. R.、 DUBUR G. YA.、 DIPAN I. V.、 CHEKAVICHUS B. S.
DOI:——
日期:——
US4239893A
申请人:——
公开号:US4239893A
公开(公告)日:1980-12-16
US4317768A
申请人:——
公开号:US4317768A
公开(公告)日:1982-03-02
σ-Bond initiated generation of aryl radicals from aryl diazonium salts
作者:Elene Tatunashvili、Bun Chan、Philippe E. Nashar、Christopher S. P. McErlean
DOI:10.1039/d0ob00205d
日期:——
transform aryl diazoniumsalts into aryl radicals. Experimental and computational studies show that Hantzsch esters transfer hydride to aryl diazonium species, and that oxygen initiates radical fragmentation of the diazene intermediate to produce aryl radicals. The operational simplicity of this addition-fragmentation process for the generation of aryl radicals, by a polar-radical crossover mechanism, has been