Asymmetric hydroamination of acrylonitrile derivatives catalyzed by Ni(II)-complexes

Chiral ferrocenyl tridentate phosphine ligands were synthesized and used in asymmetric hydroamination reactions catalyzed by Ni(II)-complexes. Compounds of the type [Ni(PPP)L]2+, where L is a chloride, solvent molecule or a coordinated substrate, were isolated. The efficiency of these complexes in asymmetric catalysis was high when aliphatic or aromatic amines were reacted with electron-poor olefins, especially with acrylonitrile derivatives. This hydroamination reaction affords up to 95% enantioselectivity at −80 °C for the addition of morpholine to methacrylonitrile (69% ee at room temperature).

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(+)-[2-(R)-Methyl-3-(morpholinium)propanenitrile][(S)-1,1′-binaphthyl-2,2′-diylphosphate]C28H27N2O5P[α]D = +335.2 (c 1, CH2Cl2)Absolute configuration: (S,R)

(−)-[2-(R)-Methyl-3-(morpholinium)propanenitrile][(R)-1,1′-binaphthyl-2,2′-diylphosphate]C28H27N2O5P[α]D = −337.3 (c 1, CH2Cl2)Absolute configuration: (R,R)

(−)-[3-(R)-(Phenylammonium)butanenitrile][(R)-1,1′-binaphthyl-2,2′-diylphosphate]C30H25N2O4P[α]D = −204.2 (c 1, CH2Cl2)Absolute configuration: (R,R)