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Phosphine catalysis review

The MBH reaction was also discussed in a general review covering nucleophilic phosphine catalysis. 2 ... [Pg.452]

In this progress report we have reviewed the latest developments in the large area of cationic low-coordinated species and their coordination with Lewis donors. It is clear that these species are of a broad interest, in particular for catalysis. In some cases, e. g. the methylene phosphenium cation, the donor adducts also open new routes for synthesis. Regarding the mechanism for the diverse donor-addition reactions, the structural details are only poorly understood and need a better classification. In particular the variation of the Lewis-donor has to be established. Hitherto in most cases iV-donation is studied. It includes amines or pyridines. Obviously the effect of other donors, such as phosphines, thioethers needs to be studied as well. The siliconium cation for which these effects are better known could provide an understanding for further investigations within this field. [Pg.91]

Primary phosphines (R-PHj) are an important ciass of compounds in organophosphorus chemistry. Aithough discovered over a century ago, their chemistry and appiications have gained prominence in recent years. This review discusses recent deveiopments on synthesis, moiecuiar structure, properties, and appiications of primary phosphines. In particular, discussions on synthesis and properties emphasize recent results from our laboratory on the chemical architecture of amide, thioether, and carboxylate functionalized primary bisphos-phines. The utility of bromo- and aminopropyl phosphines (X(CH2)3PH2 X=Br or NH2) as building blocks to produce designer primary phosphines that display exceptional oxidative stability is described. The review also discusses the utility of carboxylate functionalized primary phosphines for incorporation on to peptides and their potential applications in catalysis and biomedicine. [Pg.121]

Abstract This chapter is devoted to phosphinous amides, a particular class of tervalent aminophosphanes. First, attention is focused on their stability and synthetic procedures. Reports dealing with their prototropic equilibrium and main group chemistry are also considered. Last but not least the really important applications of these species as metal ligands in the field of catalysis are reviewed, including asymmetric variants. [Pg.77]

This review has shown that the analogy between P=C and C=C bonds can indeed be extended to polymer chemistry. Two of the most common uses for C=C bonds in polymer science have successfully been applied to P=C bonds. In particular, the addition polymerization of phosphaalkenes affords functional poly(methylenephosphine)s the first examples of macromolecules with alternating phosphorus and carbon atoms. The chemical functionality of the phosphine center may lead to applications in areas such as polymer-supported catalysis. In addition, the first n-conjugated phosphorus analogs of poly(p-phenylenevinylene) have been prepared. Comparison of the electronic properties of the polymers with molecular model compounds is consistent with some degree of n-conjugation in the polymer backbone. [Pg.124]

Miscellaneous Reactions of Phosphines.- The role of chiral phosphines as ligands in the catalysis of reactions leading to the formation of chiral products has been reviewed.1111 A procedure for the determination of the enantiomeric excess in chiral phosphines has been developed, based on 13C n.m.r. studies of the diastereoisomeric complexes formed by phosphines with the chiral pinenyl nickel bromide complex. 111 Studies of the sulphonation of triphenylphosphine and of chiral arylphosphines have been reported in attempts to prepare water soluble ligands which aid... [Pg.14]

The Ni—P bond is one of the basic motifs in Ni-based catalysis and Ni organometallic chemistry. The earlier work on phosphine-nickel complexes has been reviewed.636 The complex [Ni(dppm)Cl2] with the Ph2PCH2PPh2 (dppm) ligand is square planar. Complexes of formula... [Pg.304]

Some general reviews on hydrogenation using transition metal complexes that have appeared within the last five years are listed (4-7), as well as general reviews on asymmetric hydrogenation (8-10) and some dealing specifically with chiral rhodium-phosphine catalysts (11-13). The topic of catalysis by supported transition metal complexes has also been well reviewed (6, 14-29), and reviews on molecular metal cluster systems, that include aspects of catalytic hydrogenations, have appeared (30-34). [Pg.321]

For a review on the use of chiral mono-dentate phosphines in asymmetric catalysis, see F. Lagasse, H.B. Kagan, Chem. Pharm. Bull. 2000, 48, 315. [Pg.1024]

Hereafter, the factors ruling the activity and selectivity of Pd(II)-phosphine catalysts for the carbonylation of ethene in MeOH are presented. In order to make the exposition clearer some of the concepts already discussed in other reviews will be shortly resumed. It will deal first with copolymerisation because it includes more general aspects, several of which are involved also in the catalysis to monocarbonylated non-polymeric products. The literature search covers all up to 2004. [Pg.135]

The wide apphcation of NHCs to catalysis places them along with phosphines and cyclopentadienyls in their utility for organometaUic catalysis. Being much more donor in nature than phosphines, the NHCs occupy a distinct region of the Tolman ligand map [32]. A number of pincer NHC derivatives are catalyticaUy active, but are not discussed here because they have been fully described elsewhere [33]. Some other important recent reviews discuss catalysis by NHC complexes in general [10, 34, 35]. [Pg.49]


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Phosphine catalysis

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