952586-77-5Relevant academic research and scientific papers
ChenPhos: Highly modular P-stereogenic C1-symmetric diphosphine ligands for the efficient asymmetric hydrogenation of α-substituted cinnamic acids
Chen, Weiping,Spindler, Felix,Pugin, Benoit,Nettekoven, Ulrike
supporting information, p. 8652 - 8656 (2013/09/12)
These cats are purrfectionists: The ChenPhos ligands (see structure) showed dramatically higher catalytic activity in the title reaction than their C 2-symmetric predecessor with two dimethylaminoethyl-substituted ferrocenyl(phenyl)phosphanyl groups. The ready accessibility, extreme air stability, and high enantioselectivity, activity, and productivity of these ligands make them very promising for a wide range of practical applications. Copyright
Selective borane reduction of phosphinoferrocene carbaldehydes to phosphinoalcohol-borane adducts. the coordination behaviour of 1-(diphenylphosphino)- 1′-(methoxymethyl)ferrocene, a new ferrocene O,P-hybrid donor prepared from such an adduct
Stepnicka, Petr,Cisarova, Ivana
supporting information, p. 3373 - 3389 (2013/04/10)
The reduction of ferrocene phosphino-aldehydes, R2PfcCHO (R = Ph, 2; Cy, 3; fc = ferrocene-1,1′-diyl, Cy = cyclohexyl) and (S p)-[Fe(η5-C5H3-1-CHO-2-PPh 2)(η5-C5H5)] ((S p)-4), with BH3·THF or BH3· SMe2 in THF at 0 °C selectively afforded the corresponding phosphinoalcohol-borane adducts, R2PfcCH2OH·BH 3 (R = Ph, 5; Cy, 6) and (Sp)-[Fe(η5-C 5H3-1-CH2OH-2-PPh2) (η5-C5H5)]·BH3 ((S p)-7), in quantitative yields. In contrast, the reactions performed at elevated temperatures favoured the formation of methyl derivatives (e.g., Ph2PfcCH3·BH3 (8)) resulting from overreduction (deoxygenation). The crystal structures of 3, 5, (S p)-7, 8 and Cy2PfcBr (9) have been determined by single-crystal X-ray diffraction analysis. The crystal assemblies of adducts 5 and (Sp)-7 are built up by means of C-H...O contacts, O-H...HB dihydrogen bonds and other soft interactions but, surprisingly, not via the conventional O-H...O hydrogen bonds. Adduct 5 was smoothly deprotected to give the corresponding free phosphine, Ph2PfcCH 2OH (1), and was further used for the preparation of a hybrid phosphinoether ligand, Ph2PfcCH2OMe (11). The latter compound was studied as a donor for Group 8-10 metal ions and for Cu(i), whereupon the following complexes were isolated and structurally characterised: [(η6-p-cymene)RuCl2(11-κP)] (12*), [(η6-p-cymene)RuCl(11-κP)(MeCN)][SbF6] (13*), [RhCl(cod)(11-κP)] (cod = η2: η2-cycloocta-1,5-diene; 14), trans-[PdCl2(11-κP) 2] (trans-15*), [PdCl(μ-Cl)(11-κP)]2 (16*), cis- and trans-[PtCl2(11-κP)2] (cis-17 and trans-17*), and [Cu(CF3SO3-κO)(11- κP)(H2O)] (18) (the asterisk indicates that the crystal structure was determined). In all these compounds, ligand 11 behaves as a P-monodentate donor while its ether group remains uncoordinated. This probably reflects structural flexibility of 11 resulting from the presence of the methylene linker and also distinguishes 11 from its known, non-spaced analogue Ph2PfcOMe.
BIDENTATE CHIRAL LIGANDS FOR USE IN CATALYTIC ASYMMETRIC ADDITION REACTIONS
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Page/Page column 32-33, (2009/06/27)
Compounds of the formula (I), in the form of mixtures comprising predominantly one diastereomer or in the form of pure diastereomers, Z1-Q-P*R0R1 (I) in which Z1 is a C-bonded, secondary phosphine group -P(R)2; in which R is in each case independently hydrocarbon radicals or heterohydrocarbon radicals, or Z1 is the -P*R0R1 group; Q is a bivalent, achiral, aromatic base skeleton, a bivalent, achiral ferrocene base skeleton, an optionally substituted bivalent cycloalkane or heterocycloalkane skeleton, or a C1-C4-alkylene skeleton, and in which base skeletons a secondary phosphine group Z1 is bonded directly to a carbon atom, or, in the case of cyclic base skeletons, directly to a carbon atom or via a C1-C4-alkylene group, and in which base skeletons a P-chiral group -P*R0R1 is bonded directly to a carbon atom, or, in the case of cyclic base skeletons, directly to a carbon atom or via a C1-C4-alkylene group to a carbon atom such that the phosphorus atoms are linked via 1 to 7 atoms of a carbon chain optionally interrupted by heteroatoms from the group of O, S, N, Fe or Si; P* is a chiral phosphorus atom; R0 is methyl or hydroxyl, and R0 is methyl when Z1 is the -P*R0R1 group; and R1 is a C-bonded optically enriched or optically pure chiral, mono- or polycyclic, nonaromatic hydrocarbon or heterohydrocarbon radical which has 3 to 12 ring atoms and 1 to 4 rings and which has a stereogenic carbon atom at least in the α position to the P-C bond; Metal complexes of these ligands are homogeneous catalysts for asymmetric addition reactions, particularly hydrogenations.
CHIRAL LIGANDS USED IN TRANSITION METAL CATALYSTS FOR ASYMMETRIC ADDITION REACTIONS ESPECIALLY HYDROGENATION
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Page/Page column 38, (2008/06/13)
Ligands of the formula (I) secondary phosphine-Q-P(=O)HR1 (I) in the form of mixtures of diastereomers or pure diastereomers, in which secondary phosphine is a secondary phosphine group with hydrocarbon radicals or heterohydrocarbon radicals as substituents; Q is a bivalent bisaryl or bisheteroaryl radical with an axial chiral centre to which the two phosphorus atoms are bonded in the ortho positions to the bisaryl or bisheteroaryl bridge bond, or Q is a bivalent ferrocenyl radical with a planar chiral centre or without a planar chiral centre, to which the phosphorus atom of the secondary phosphine is bonded directly or via a C1-C4-carbon chain to a cyclopentadienyl ring, the -P*(=O)HR1 group is bonded either on the same cyclopentadienyl ring in ortho position to the bonded secondary phosphine or on the other cyclopentadienyl ring; P* is a chiral phosphorus atom, and R1 is a hydrocarbon radical, a heterohydrocarbon radical or a ferrocenyl radical, where R1 is a ferrocenyl radical with a planar chiral centre when Q is a ferrocenyl radical without a planar chiral centre. Metal complexes of these ligands are homogeneous catalysts for asymmetric addition reactions, particularly hydrogenations.
FERROCENEDIPHOSPHINES
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Page/Page column 29; 38-39, (2008/06/13)
Compounds of the formula I in the form of enantiomerically pure diastereomers or a mixture of diastereomers, (I), where the radicals R1 are identical or different and are each C1-C4-alkyl; m is 0 or an integer from 1 to 3; n is 0 or an integer from 1 to 4; R2 is a hydrocarbon radical or a C-bonded heterohydrocarbon radical; Cp is unsubstituted or C1-C4-alkyl-substituted cyclopentadienyl; Y is a C-bonded chiral group which directs metals of metallation reagents into the ortho position; and Phos is a P-bonded P(III) substituent. The compounds are chiral ligands for complexes of transition metals which are used as homogeneous catalysts in asymmetric syntheses.
