Platinum(0) Complexes of Chiral Diphosphines: Enantioface-Selective Binding of trans-Stilbene
journal contributionposted on 1998-03-12, 00:00 authored by Denyce K. Wicht, Michael A. Zhuravel, Ronald V. Gregush, David S. Glueck, Ilia A. Guzei, Louise M. Liable-Sands, Arnold L. Rheingold
The zerovalent complexes Pt(diphos)(trans-stilbene) (diphos = dppe, dppf, (S,S)-Chiraphos, R-Tol-Binap, (R,R)-Me-Duphos, (S,S)-Diop) were prepared by reduction of the corresponding Pt(diphos)Cl2 compounds. NMR and crystal structure data show that the trans-stilbene complexes with chiral diphosphines exist as a mixture of diastereomers differing in their binding of the enantiofaces of the prochiral olefin; for R-Tol-Binap, they can be separated by recrystallization. The complexes Pt((R,R)-Me-Duphos)Cl2 and Pt(diphos)(trans-stilbene) (diphos = dppf, (S,S)-Chiraphos, R-Tol-Binap, (S,S)-Diop) were structurally characterized by X-ray crystallography.