Cyclopentadienyl complex isonitrile

Despite a common perception that organometallic chemistry essentially belongs in the province of catalysis rather than in vivo applications because of high reactivity of metal carbon bonds, certain organometallic species have very high kinetic stability. Indeed, this point is highlighted by the present wide application of the isonitrile complex Tc(ses-tamibi), [Tc(2-methoxyisobutylisonitrile)6]+, in myocardial imaging. Rhenium tricarbonyl and cyclopentadienyl complexes offer further ex-... 

Although carbonyl and cyclopentadienyl complexes are well known for Tc(I) and Tc(III), none appear to have been reported for Tc(II). This may be ascribed to the tendency to follow the 18-electron rule, which, due to the odd number of electrons, would require dimer formation for compliance. Similarly, no Tc(II) cyano or isonitrile complexes appear to have been isolated. 

Cyclopentadienyl Complexes Cyano, Isonitrile, and Thiocyanate Complexes Aqua, Halide, and Related Dimeric Complexes Carboxylato and /3-Diketonato Complexes... 

The six-coordinate tris(benzamidinates) [PhC(NSiMe3)2]3Ln also form 1 1 adducts with donor ligands such as THF, MeCN, or PhCN. In the case of ben-zonitrile, it was possible to isolate and structurally characterize two of these seven-coordinated nitrile-adducts. They are most readily isolated when the original preparation is directly carried out in the presence of one equivalent of benzonitrile (Scheme 15). The facile adduct formation with small donor molecules is yet another analogy between the tris(amidinates) and the tris(cyclopentadienyl) complexes, for which similar adducts with, for example, THF, nitriles or isonitriles are well established [6,7,17]. 

Heterometal alkoxide precursors, for ceramics, 12, 60-61 Heterometal chalcogenides, synthesis, 12, 62 Heterometal cubanes, as metal-organic precursor, 12, 39 Heterometallic alkenes, with platinum, 8, 639 Heterometallic alkynes, with platinum, models, 8, 650 Heterometallic clusters as heterogeneous catalyst precursors, 12, 767 in homogeneous catalysis, 12, 761 with Ni—M and Ni-C cr-bonded complexes, 8, 115 Heterometallic complexes with arene chromium carbonyls, 5, 259 bridged chromium isonitriles, 5, 274 with cyclopentadienyl hydride niobium moieties, 5, 72 with ruthenium—osmium, overview, 6, 1045—1116 with tungsten carbonyls, 5, 702 Heterometallic dimers, palladium complexes, 8, 210 Heterometallic iron-containing compounds cluster compounds, 6, 331 dinuclear compounds, 6, 319 overview, 6, 319-352... 

Whereas amino groups are used most frequently as intramolecular Lewis bases (Tables 5-7), stable unsupported intermolecular complexes are typically accomplished by carbene-type donors, such as carbenes, isonitriles and ylides (Table 8). To my knowledge, no unsupported intermolecular adduct of ethers, amines or phosphanes have been structurally characterized so far (except for the more ionic cyclopentadienyl derivatives62). 

However, 7t-cyclopentadienyl-7t-allylpalladium can be used to prepare an isonitrile-palladium complex " ... 

Cyclopentadienyl and Arene Complexes Cyano and Isonitrile Complexes... 

Bis(cyclopentadienyl)titanium(n) Dicarbonyl, Isonitrile, and Phosphine Complexes 250... 

Tricyclopentadienyl rare earth cyclohexyl isonitrile complexes have been prepared by addition of cyclohexyl isonitrile to the corresponding tris(cyclopentadienyl) rare earth compounds in benzene. They show definite melting points and are sublimable in vacuum at about 150 to 160°C (E.O. Fischer and H. Fischer, 1965a, 1966 Von Ammon and Kanellakopulos, 1972) ... 

The cyclohexyl isonitrile complexes of the tris(methylcyclopentadienyl) cerium, praseodymium, and neodymium compounds have been mentioned in a discussion of the NMR spectra of these and the corresponding tricyclopentadienyl rare earth complexes, which showed that the AG values of the fluxionality of the cyclohexyl ligands decreased in contrast to those of the unsubstituted cyclopentadienyl derivatives (R.D. Fischer, 1979). 

The reaction of palladium indenyl complexes with isonitriles leads to the synthesis of palladium fulvenes (Scheme 86). The reaction seems to occur by decoordination of the indenyl fragment, and the resulting indenide attacks a coordinated isonitrile. An analogous reaction takes place when cyclopentadienyl is used. ... 

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