1,4-Asymmetric Induction in Methoxyselenenylation of Double Bonds at the Nitrogen Side of Chiral Perhydro-1,3-benzoxazines Promoted by Nonbonded Se···N Interactions
cinnamylamines attached to a chiral perhydrobenzoxazine occurs in high yields by reaction with benzeneselenenyl chloride in dichloromethane−methanol. The diastereoselection is dependent on the temperature of the reaction and the structure of the substituent at C-2 and can be rationalized by accepting a 1,4-asymmetricinduction process after coordination of the selenium to the nitrogen atom of the allylamine
Perhydro-1,3-benzoxazines derived from (−)-8-aminomenthol as ligands for the catalytic enantioselective addition of diethylzinc to aldehydes
作者:Celia Andrés、Rebeca Infante、Javier Nieto
DOI:10.1016/j.tetasy.2010.07.016
日期:2010.9
The catalytic potency of a series of perhydro-1,3-benzoxazines prepared from (−)-8-aminomenthol was examined in the enantioselective addition of diethylzinc to aldehydes. When (2R,3S,3aS,4aR,6R,8aS)-2-isopropyl-6,9,9-trimethyl-3-phenyldecahydro-4aH-pyrrolo[2,1-b][1,3]benzoxazin-3-ol 7b was used as a chiral ligand, 1-substituted propanols with an (R)-configuration were obtained in high yields and enantiomeric