Remote Stereocontrol Mediated by a Sulfinyl Group: Synthesis of Allylic Alcohols via Chemoselective and Diastereoselective Reduction of γ-Methylene δ-Ketosulfoxides
作者:José L. García Ruano、M. Ángeles Fernández-Ibáñez、José A. Fernández-Salas、M. Carmen Maestro、Pablo Márquez-López、M. Mercedes Rodríguez-Fernández
DOI:10.1021/jo802378s
日期:2009.2.6
diastereoselectivity of the reduction of α,β-unsaturated α-[2-(p-tolylsulfinyl)phenyl] substitutedketones 1 has been demonstrated in reactions carried out under NaBH4 in the presence of Yb(OTf)3 as the chelating agent. The starting unsaturated ketones have been prepared from the corresponding 2-(p-tolylsulfinyl) benzyl alkyl (and aryl) ketones 2 by insertion of the methylidene group under modified Mannich conditions
Remote stereocontrol by sulfinyl groups: hydrocyanation of δ-ketosulfoxides
作者:José L. García Ruano、M. Ángeles Fernández-Ibáñez、M. Carmen Maestro、M. Mercedes Rodríguez-Fernández
DOI:10.1016/j.tet.2005.10.067
日期:2006.2
Et2AlCN in the presence of Yb(OTf)3 take place in a completely stereoselective manner, demonstrating the efficiency of the sulfinyl group in the control of the stereoselectivity of 1,5-asymmetric hydrocyanation processes as well as the ability of Yb(OTf)3 to form chelated species with ketosulfoxides. The behavior of their methylderivatives at the benzylic position is dependent on the configuration at
Remote Stereocontrol by Sulfinyl Groups: Reduction of δ-Ketosulfoxides
作者:José L. García Ruano、M. Ángeles Fernández-Ibáñez、M. Carmen Maestro、M. Mercedes Rodríguez-Fernández
DOI:10.1021/jo047999j
日期:2005.3.1
[GRAPHICS]The reduction of delta-ketosulfoxides constitutes the first evidence of the efficiency of the sulfinyl group to control the stereoselectivity of 1,5-asymmetric induction processes. The use of DIBAL/Yb(OTf)(3) or L-Selectride as the reducing agents provides delta-hydroxysulfoxides with the opposite configuration at the hydroxylic carbon in a highly stereoselective way.