@article {392,
	title = {Synthesis, characterization, and solution redox properties of (trimpsi)M(CO)(2)(NO) complexes [M = V, Nb, Ta; trimpsi = (BuSi)-Bu-t(CH2PMe2)(3)]},
	journal = {Inorganic Chemistry},
	volume = {41},
	number = {16},
	year = {2002},
	note = {ISI Document Delivery No.: 582RTTimes Cited: 7Cited Reference Count: 85},
	month = {Aug},
	pages = {4114-4126},
	type = {Article},
	abstract = {{Treatment of [Et4N][M(CO)(6)] (M = Nb, Ta) with I-2 in DME at -78 degreesC produces solutions of the bimetallic anions [M-2(mu-l)(3)(CO)(8)](-). Addition of the tripodal phosphine (BuSi)-Bu-t(CH2PMe2)(3) (trimpsi) followed by refluxing affords (trimpsi)M(CO)(3)I [M = Nb (1), Ta (2)], which are isolable in good yields as air-stable, orange-red microcrystalline solids. Reduction of these complexes with 2 equiv of Na/Hg, followed by treatment with Diazald in THF, results in the formation of (trimpsi)M(CO)(2)(NO) [M = Nb (3), Ta (4)] in high isolated yields. The congeneric vanadium complex, (trimpsi)V(CO)(2)(NO) (5), can be prepared by reacting [Et4N][V(CO)(6)] with [NO][BF4] in CH2Cl2 to form V(CO)(5)(NO). These solutions are treated with 1 equiv of trimpsi to obtain (eta(2)-trimpsi)V(CO)(3)(NO). Refluxing orange THF solutions of this material affords 5 in moderate yields. Reaction of (trimpsi)VCl3(THF) (6) with 4 equiv of sodium naphthalenide in THF in the presence of excess CO provides [Et4N][(trimpsi)V(CO)(3)] (7), (trimpsi)V(CO)(3)H, and [(trimpsi)V(mu-Cl)(3)V(trimpsi)][(eta(2)-trimpsi)V(CO)(4)].3THF ([8][9].3THF). All new complexes have been characterized by conventional spectroscopic methods, and the solid-state molecular structures of 2.(1)/2THF, 3-5, and [8][9].3THF have been established by X-ray diffraction analyses. The solution redox properties of 3-5 have also been investigated by cyclic voltammetry. Cyclic voltammograms of 3 and 4 both exhibit an irreversible oxidation feature in CH2Cl2 (E-p},
	keywords = {CHARACTERIZATION, CHEMISTRY, DERIVATIVES, HIGHLY REDUCED ORGANOMETALLICS, ISOCYANIDE COMPLEXES, NITRIC-OXIDE, PHOSPHINE COMPLEXES, RAY CRYSTAL-STRUCTURES, SPECTROSCOPIC, tantalum, VANADIUM(II)},
	isbn = {0020-1669},
	url = {<Go to ISI>://000177365500013},
	author = {Hayton, T. W. and Daff, P. J. and Legzdins,Peter and Rettig, S. J. and Patrick, B. O.}
}
@article {4159,
	title = {Homoleptic metal carbonyl cations of the electron-rich metals: Their generation in superacid media together with their spectroscopic and structural characterization},
	journal = {Angewandte Chemie-International Edition in English},
	volume = {36},
	number = {22},
	year = {1997},
	note = {ISI Document Delivery No.: YK253Times Cited: 18Cited Reference Count: 279},
	month = {Dec},
	pages = {2403-2425},
	type = {Review},
	keywords = {ANIONS, carbonyl complexes, CATIONS, CESIUM, FLUOROSULFATE, FLUOROSULFATE DERIVATIVES, GOLD(III), HEXAKIS(FLUOROSULFATO)ANTIMONATE(V), HIGHLY REDUCED ORGANOMETALLICS, MAS-NMR-SPECTRA, MOLECULAR-STRUCTURE, superacidic systems, synthetic methods, transition metals, TRANSITION-ELEMENTS, TRIFLUOROMETHYLATED, TRIS(PYRAZOLYL)BORATE, VIBRATIONAL-SPECTRA, WEAKLY COORDINATING},
	isbn = {0570-0833},
	url = {<Go to ISI>://A1997YK25300001},
	author = {Willner, H. and Aubke, F.}
}
@article {2956,
	title = {CARBON-MONOXIDE AS A SIGMA-DONOR LIGAND IN COORDINATION CHEMISTRY},
	journal = {Coordination Chemistry Reviews},
	volume = {137},
	year = {1994},
	note = {ISI Document Delivery No.: PW818Times Cited: 84Cited Reference Count: 189},
	month = {Dec},
	pages = {483-524},
	type = {Review},
	abstract = {In addition to the numerous and varied examples of organometallic and coordination compounds where carbon monoxide functions as a pi-acceptor ligand, there is a small but select group of derivatives where the CO-metal bonding relies predominantly on a-bonding only. The metal derivatives, which include Pt(CO)(2)Cl-2 known since 1868, are formed by electron-rich metals (Pd, Pt, Ag and Au), in oxidation states +1 and +2, are cationic in nature, and are for the most part thermally stable. Their generation in strong protonic and Lewis acids (HSO3F, HSO3F-SbF5 and liquid SbF5) allows convenient synthesis. The predominance of sigma-bonding results in unusual spectroscopic properties, such as <(nu)over bar>CO stretching vibrations as high as 2280 cm(-1), relative to 2143 cm(-1) in free CO, and C-13 chemical shifts which are 180-130 ppm rather than 190-220 ppm for classical transition-metal carbonyls. Consequently two basic principles, the synergic bonding model and the rule of 18, fail for these complexes. Recent structural studies point to the importance of secondary OC...OS or OC...FSb contacts, which in place of pi-backdonation provide for a measure of charge compensation both in solution or in the solid state. This review concentrates on very recent (since 1990) developments in this field, which is expanding rapidly beyond the transition metals.},
	keywords = {FLUOROSULFATE DERIVATIVES, GOLD(III) FLUOROSULFATE, HIGHLY REDUCED ORGANOMETALLICS, LATE TRANSITION-ELEMENTS, MAGNETIC-PROPERTIES, MICROWAVE-SPECTRUM, MOLECULAR-STRUCTURE, NOBLE-METALS, THIONYL CHLORIDE, VIBRATIONAL-SPECTRA},
	isbn = {0010-8545},
	url = {<Go to ISI>://A1994PW81800013},
	author = {Aubke, F. and Wang, C.}
}
