Binap-Gold(I) versus Binap-Silver Trifluoroacetate Complexes as Catalysts in 1,3-Dipolar Cycloadditions of Azomethine Ylides
作者:María Martín-Rodríguez、Carmen Nájera、José M. Sansano、Abel de Cózar、Fernando P. Cossío
DOI:10.1002/chem.201101606
日期:2011.12.9
The 1,3‐dipolarcycloaddition between azomethine ylides and alkenes is efficiently catalysed by [(Sa)‐Binap‐Au(tfa)}2] (Binap=2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl; tfa=trifluoroacetyl). Maleimides, 1,2‐bis(phenylsulfonyl)ethylene, chalcone and nitrostyrene were suitable dipolarophiles even when using sterically hindered 1,3‐dipole precursors. The results obtained in these transformations improve
Binap-silver salts as chiral catalysts for the enantioselective 1,3-dipolar cycloaddition of azomethine ylides and alkenes
作者:Juan Mancebo-Aracil、María Martín-Rodríguez、Carmen Nájera、José M. Sansano、Paulo R.R. Costa、Evanoel Crizanto de Lima、Ayres G. Dias
DOI:10.1016/j.tetasy.2012.10.015
日期:2012.12
Binap-AgSbF6 catalyzed 1,3-dipolarcycloadditions between azomethineylides and electrophilicalkenes are described and compared with analogous transformations mediated by other Binap-silver(I) salt complexes. Maleimides and 1,2-bis(phenylsulfonyl)ethylene are suitable dipolarophiles for obtaining very good enantioselectivities, even better values are generated by a multicomponent version. There are