65220-78-2Relevant academic research and scientific papers
Phosphine-borane complexes; Direct use in asymmetric catalysis
Brisset,Gourdel,Pellon,Le Corre
, p. 4523 - 4526 (1993)
An easy and soft method of decomplexation of phosphine-borane complexes, by DABCO, allows its use in situ in asymmetric catalytic hydrogenation of double bonds with metal phosphine complexes.
Streamlined Preparation and Coordination Chemistry of Hybrid Phosphine-Phosphaalkene Ligands
Magnuson, Kevin W.,Oshiro, Shelly M.,Gurr, Joshua R.,Yoshida, Wesley Y.,Gembicky, Milan,Rheingold, Arnold L.,Hughes, Russell P.,Cain, Matthew F.
supporting information, p. 855 - 859 (2016/04/19)
A rationally designed and selective synthesis of hybrid phosphine-phosphaalkene ligands E-1a (Cy2PCH2CH = PMes?, Mes? = 2,4,6-tri-tert-butylphenyl) and E-1b (Ph2PCH2CH = PMes?) was developed using phospha-Wittig methodology. The new hybrid ligands E-1a and E-1b were used to prepare the Pd and Pt dichloride complexes Pd(Cy2PCH2CH = PMes?)Cl2 (2a), Pd(Ph2PCH2CH = PMes?)Cl2 (2b), Pt(Cy2PCH2CH = PMes?)Cl2 (3a), and Pt(Ph2PCH2CH = PMes?)Cl2 (3b). The crystal structures of E-1a, E-1b, 2a·1.33CHCl3, 3a·CH3CN, and 3b were determined. DFT calculations (M06/LACV3PMes??) on 2a revealed that the π? orbital located on the P = C unit is low-lying and accessible. An NBO analysis concluded that the phosphaalkene ligand is a significantly poorer σ donor and a slightly better π acceptor than its tertiary phosphine counterpart, due to the presence of the P = C double bond.
Amine(imine)diphosphine iron catalysts for asymmetric transfer hydrogenation of ketones and imines
Zuo, Weiwei,Lough, Alan J.,Li, Young Feng,Morris, Robert H.
, p. 1080 - 1083 (2014/01/06)
A rational approach is needed to design hydrogenation catalysts that make use of Earth-abundant elements to replace the rare elements such as ruthenium, rhodium, and palladium that are traditionally used. Here, we validate a prior mechanistic hypothesis that partially saturated amine(imine)diphosphine ligands (P-NH-N-P) activate iron to catalyze the asymmetric reduction of the polar bonds of ketones and imines to valuable enantiopure alcohols and amines, with isopropanol as the hydrogen donor, at turnover frequencies as high as 200 per second at 28°C. We present a direct synthetic approach to enantiopure ligands of this type that takes advantage of the iron(lI) ion as a template. The catalytic mechanism is elucidated by the spectroscopic detection of iron hydride and amide intermediates.
