Chiral phosphine-catalyzed regio- and enantioselective allylic amination of Morita–Baylis–Hillman acetates

Enantioselective allylic substitution of Morita–Baylis–Hillman (MBH) acetates with phthalimide was realized in the presence of a novel l-proline-derived chiral trifunctional phosphine amide ligand to give the corresponding allylic amination adducts in good yields (70–95%) and in modest to good enantioselectivities (34–78% ee’s).

Figure optionsDownload as PowerPoint slide

(S)-tert-Butyl-2-((R)-2′-(diphenylphosphino)-1,1′-binaphthyl-2-ylcarbamoyl)pyrrolidine-2-carboxylateC42H39N2O3PEe = 100%[α]D20=-22.4 (c 0.91, CHCl3)Source of chirality: (R)-BINOL, l-prolineAbsolute configuration: (1R,2S)

(2S)-N-((R)-1-(2-(Diphenylphosphino)naphthalen-1-yl)naphthalen-2-yl)pyrrolidine-2-carboxamideC37H31N2OPEe = 100%[α]D20=-11.4 (c 2.18, CHCl3)Source of chirality: (R)-BINOL, l-prolineAbsolute configuration: (1R,2S)

(2R)-N-((R)-1-(2-(Diphenylphosphino)naphthalen-1-yl)naphthalen-2-yl)pyrrolidine-2-carboxamideC37H31N2OPEe = 100%[α]D20=+20.1 (c 0.53, CHCl3)Source of chirality: (R)-BINOL, d-prolineAbsolute configuration: (1R,2R)