Chan, Vincent S. et al. published their research in Journal of the American Chemical Society in 2009 | CAS: 133545-16-1

(R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1) belongs to chiral phosphine ligands. The synthesis of novel trialkylphosphines can be quite difficult, thereby limiting the scope of their chiral variants. Chiral phosphine catalysts: Nucleophilic phosphine catalysis often involves the formation of Lewis adducts, namely phosphonium (di)enolate zwitterions, as reaction intermediates.Product Details of 133545-16-1

Development of ruthenium catalysts for the enantioselective synthesis of P-stereogenic phosphines via nucleophilic phosphido intermediates was written by Chan, Vincent S.;Chiu, Melanie;Bergman, Robert G.;Toste, F. Dean. And the article was included in Journal of the American Chemical Society in 2009.Product Details of 133545-16-1 This article mentions the following:

Ruthenium chiral diphosphine complexes [L2RuH][BPh4] or [(L1)(dmpe)RuH][BPh4] [L, L1 = chiral diphosphines, dmpe = 1,2-bis(dimethylphosphino)ethane] catalyze base-promoted low-temperature asym. alkylation of secondary phosphine PhMePH by benzyl halides, yielding chiral PhMe(ArCH2)P (Ar = Ph, 4-ClC6H4, 4-MeC6H4, 4-MeOC6H4, 2-MeC6H4, 1-naphthyl, 2-pyridinyl, 2-furanyl) or diphosphines PhMePCH2Ar1CH2PMePh (Ar1 = 1,3-phenylene, 1,2-phenylene, 1,3-pyridinediyl) with up to 80% ee [L = 4-iPr-2-(C6H4PPh2-2)oxazoline (iPr-PHOX) or L1 = MeO-BiPHEP, SEGPHOS]. The optimized base for the reaction was found to be sodium tert-amylate, which prevents the occurrence of background non-catalytic alkylation by deprotonation of uncoordinated PhMePH. The reactions proceed through the intermediacy of nucleophilic phosphido species, which have low barriers to pyramidal inversion; this allows for a dynamic kinetic asym. alkylation. The initially discovered [((R)-iPr-PHOX)2Ru(H)][BPh4] (6) catalyst was found to be effective in the reaction with benzylic chlorides; moreover, the alkylation displayed an unusual temperature dependence. However, the limited scope of alkylation of 6 motivated further studies which led to the development of two complementary chiral mixed ligand Ru(II) catalysts of type [L1L2Ru(H)]+. These catalysts were derived from a combination of one chiral and one achiral ligand, where a synergistic interaction of the two ligands creates an effective asym. environment around the ruthenium center. The (R)-MeO-BiPHEP catalyst [((R)-MeO-BiPHEP)(dmpe)RuH][BPh4] (10) was found to be effective for the asym. alkylation by benzyl chlorides, while the (R)-DIFLUORPHOS catalyst [[(R)-DIFLUORPHOS](dmpe)RuH][BPh4] (11) was optimal for the nucleophilic substitution of less activated alkyl bromides; the scope of the resp. catalysts was also explored. In the experiment, the researchers used many compounds, for example, (R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1Product Details of 133545-16-1).

(R)-(6,6′-Dimethoxy-[1,1′-biphenyl]-2,2′-diyl)bis(diphenylphosphine) (cas: 133545-16-1) belongs to chiral phosphine ligands. The synthesis of novel trialkylphosphines can be quite difficult, thereby limiting the scope of their chiral variants. Chiral phosphine catalysts: Nucleophilic phosphine catalysis often involves the formation of Lewis adducts, namely phosphonium (di)enolate zwitterions, as reaction intermediates.Product Details of 133545-16-1

Referemce:
Phosphine ligand,
Chiral phosphines in nucleophilic organocatalysis