Tertiary phosphines and phosphites

Tertiary phosphines are used widely as deoxygenating reagents in preparative coordination chemistry. Their reactivity toward the oxygen atom is due to the high energy of the P=0 bond in the corresponding phosphoranes (120-150 kcal/mol).i33 Chart was one of the first to use tertiary phosphines as 

The deoxygenation of Re207 by triethylphosphine proceeds differently in pyridine, Eq. 9.36 13  

Additional examples of deoxygenation of Re=0 complexes have been reported by Herrmann and coworkersl37-140 ho have shown that a homobinuclear complex of rhenium(V) is formed as a result of partial 

Reduction of a rhenium(V) 0x0 complex with P(OEt)3 has been described.141 [ReOCl3(py)2] was refluxed with a twenty-fold molar excess of triethylphosphite in benzene which resulted in a two-electron reduction of the metal center and formarton of [ReCl3 P(OEt)3)3]. Further, a similar 

The kinetics of oxygen atom transfer from a Mo(VI) complex to tertiary phosphines has been studied by Holm, Reynolds, and Berg. 45-147 They found that the rate constant of the reaction, Eq. 9.37  

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A number of ruthenium(II) complexes have been prepared. Cole-Hamilton and Stephenson isolated cts-[Ru(Me2dtc)2L2] (L = PPhj, PMe2, Ph, PPhMe2, or P(OPh)3) from Ru(II) and Ru(III) tertiary phosphine and phosphite complexes with NaMe2dtc, and found that they undergo rearrangements (288). 

In the tetranuclear clusters significant steric control of substitution with tertiary phosphines and phosphites is generally only observed in the fourth substitution step. The synthesis of tetra-substituted derivatives, therefore, requires more severe conditions22,46,86,248 and then breaking of the cluster can become important. 

TRI- AND TETRANUCLEAR CARBONYL-RUTHENIUM CLUSTER COMPLEXES CONTAINING ISOCYANIDE, TERTIARY PHOSPHINE, AND PHOSPHITE LIGANDS. RADICAL ION-INITIATED SUBSTITUTION OF METAL CLUSTER CARBONYL COMPLEXES UNDER MILD CONDITIONS... 

Reactions of H9FeRu (C0)iWith Tertiary Phosphines and Phosphites. H2FeRu3(C0)i3 reacts with a series of tertiary phosphine and phosphite ligands to yield mono- and disubstituted clusters in 20-30% yield, eq. 8 (18). 

From the palladium (0) di-isocyanides a complete replacement could easily be obtained (129) with tertiary phosphines and phosphites. 

By Reduction. The first reducing agents used to prepare the platinum (0) ISOy 183) and palladium (0) 129) derivatives with tertiary phosphines and phosphites were hydrazine and ethanolic potassium hydroxide. 

Reports of nucleophilic attack at atoms other than those above have also appeared. A kinetic study has compared the effectiveness of tertiary phosphines and phosphite esters in the catalysis of the cleavage of the silicon-silicon bond of methylchlorodisilanes, providing evidence for the involvement of a stabilised silylene intermediate. The anion of the y-phosphino-p-diketimine (197) has been shown to react with arsenic trichloride to give the phosphino-arsino-p-diketimine (198), in which there is a coordinative link from phosphorus to arsenic. ... 

Carbon monoxide insertions promoted by tertiary phosphines and phosphites were reported for the iron(II) complex Fe(t -C5H5)Me(CO)2 ... 

Kinetic studies have been reported for the additions of some tertiary phosphines and phosphites and the highly basic amines nicotine and 1-phenylethyl-amine on the cyclohexadienyl cation [Fe(CO) (rf -Cf,lV)y (38). Combination with earlier kinetic data for related reactions (10) has established a comprehen-... 

Molybdenum and tungsten complexes of the type [M(SR(GP30CCF3)2Cp)] have been reacted with tertiary phosphines and phosphites and alkynes and the related conqilexes [M ii -C(CF3)C(CF3)SR)(CF3CsCCF3)(Cp)], M = Mo, W R Me, Pr, Bu have been reacted with alkyncs to give a series of new ii -vinyl or Ti -butadienyl complexes. Nucleophilic additions to [CpMo(CO)2(Ti -cyclq)entadienone)] salts yield a series of stable neutral coiqilexes containing the ii -o-substituted cyclt ntenoyl products. ... 

Kinetic studies have been made of the reactions of dimetal carbonyls of the type [M2(CO)io L ] (M2 = Mn2, MnRe, Re2 n = 1 or 2 L = range of tertiary phosphines and phosphites) with bromine and iodine in cyclohexane or de-calin. Complex rate laws were obtained, usually in the iodine case containing a predominant kih] term, but a term as high as [12] was obtained in one case. The influence of L on the rate constants for both I2 and Br2 reactions was best interpreted in terms of initial electrophilic attack at the O atom of the CO ligands. Rates increased in the order Mn2 < MnRe < Re2. 

Table 15. Some literature data on tertiary phosphines and phosphites binding to haems...

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