Zinc-mediated asymmetric additions of dialkylphosphine oxides to α,β-unsaturated ketones and N-sulfinylimines.
A catalyst was synthesized on the basis of Trost's dinuclear catalyst characterized by working well without pyridine in the present phospha-Michael reaction. Nevertheless, the presence of pyridine is still advantageous in the present system. The substrate scope was successfully extended to enones employing diallyl phosphine oxide as a nucleophile. Excellent yields and enantioselectivities (up to >99% ee) were achieved for a wide scope of enones employing the catalyst under mild conditions. The detailed reaction mechanism is also discussed herein. Finally, the unprecedented asymmetric additions of dialkylphosphine oxides to N-sulfinylimines were achieved by using Et(2)Zn as a base.
Zhao
Depeng
D
Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Medicine, State Key Laboratory of Applied Organic Chemistry, and Institute of Biochemistry and Molecular Biology, Lanzhou University, Lanzhou 730000, PR China.
Mao
Lijuan
L
Yang
Dongxu
D
Wang
Rui
R
D002384:Catalysis; D007097:Imines / Q000138:chemical synthesis / Q000737:chemistry*; D007659:Ketones / Q000138:chemical synthesis / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D010720:Phosphines / Q000737:chemistry*; D013237:Stereoisomerism; D015032:Zinc / Q000737:chemistry*
D007097:Imines; D007659:Ketones; D009942:Organometallic Compounds; D010087:Oxides; D010720:Phosphines; D015032:Zinc