Re , carbonyl complexes

However, while RE carbonyl complexes are not bottleable, they have been detected under matrix isolation conditions in frozen argon matrixes or in CO atmosphere high-pressure studies. Binary RE carbonyls, [M(CO) ] (n = 1-6), have been observed with some evidence for the formation of M(CO) (n = 7 or 8) species. These binary RE carbonyl adducts typically exhibit a single carbonyl stretch which is 145 195 cm lower than the stretching frequency of 2134 cm for free CO. Backbonding could be assumed to operate, which is reasonable for RE metals in a formal zero-oxidation state where valence orbitals are more chemically accessible. However, it has been noted that the infrared (IR) spectra of all binary RE carbonyls across the RE series... 

With the low-valence iron pentacarbonyl, vinylcyclopropanes 22 are thermally transformed to the diene re-complexes, the (1,3-trans-pentadiene)iron carbonyl complexes 23, through bond fission, 1,2-hydrogen shift, and stereoselective coordination [15]. (Scheme 9)... 

The related iron carbonyl complex 55 was obtained by the reaction of [Fe3(CO)i2] with C(PPh3)(CO) however, according to [95] it is questionable because the spectroscopic data do not match with those of related compounds. The Mn and Re complexes [Cp(CO)2M C(PPh3)(CO) ] (M = Mn (56), Re (57)) have also been reported the ylide replaces the labile ether ligand in [Cp(CO)2M (OEt2)] [142]. The examples with the bonded ketenylidene ligand C(PPh3)(CO) are summarized in Fig. 30. 

The use of carbonyl complexes has enabled proper study of the role of rhenium in Pt-Re bimetallic catalysts used in the reforming of naphtha [57-60] and tailoring of the preparation of Pt-Ru bimetallic particles. Pt-Ru systems are of interest in developing electrodes for fuel cell applications [61]. 

Table 16.1 Synthesis of some Re, Fe and Ru carbonyl complexes and clusters on the surface of Si02, MgO or...

The first thionitrosyl complex was discovered by chance during an attempted synthesis of molybdenum nitrido complexes in the presence of a source of sulfur, tetrathiuram sulfide.168 This work of Dilworth and Chatt was reported in 1974 and ultimately led to the syntheses of a range of Mo, Re and Os thionitrosyl complexes starting with the respective nitrido complexes.143,164 Nitrosyl complexes, like carbonyls, had been known for decades, and the more recent syntheses of thio-carbonyl complexes forebode the advent of thionitrosyl complexes. However, convenient synthetic routes based on analogies with syntheses of NO complexes were generally not available because the requisite precursors did not exist or were inconvenient to handle. Sulfiliminato complexes (M=N=SR2) of transition metals are as yet unknown. The chemistry of thionitrosyl complexes was the subject of a recent review.179... 

Carbonyl complexes with actinides, 4, 192 (7 5-acyclic)Re(CO)3 complexes, 5, 919 allylation, 10, 663 with allylic tins, 9, 354 into 7 3-allyl palladium complexes, 8, 364 arene chromium carbonyls... 

Rhenium carbonyl complexes were used as probes in biological systems. Photoexcitation of [Re(phen)(CO)3(H83)]+AzM2+ and [Re(phen)(CO)3(H107)] + AzM2+ (Az = Pseudomonas aeruginosa azurin M = Cu or Zn) in the presence of the oxidative quencher, Co(NH3)5C1, resulted in the formation... 

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