@article {4545,
	title = {Preparation and reactivity of zirconium(III), niobium(III), and molybdenum(III) complexes stabilized by a cyclopentadienyl unit with pendant phosphine donors},
	journal = {Organometallics},
	volume = {18},
	number = {20},
	year = {1999},
	note = {ISI Document Delivery No.: 244CDTimes Cited: 14Cited Reference Count: 55},
	month = {Sep},
	pages = {4050-4058},
	type = {Article},
	abstract = {This paper deals with the organometallic chemistry of the trivalent second-row transition metals of groups 4-6, namely, Zr, Nb, and Mo, with the cyclopentadienyldiphosphine ligand [eta(5)-C5H3-1,3-(SiMe2CH2PR2)(2)], abbreviated as [(P2Cp)-P-R] (where R = i-Pr and Ph). The Zr(IV) complex [i-PrP2Cp]ZrCl3 undergoes reduction with Na/Hg to form the trivalent Zr derivative, [i-PrP2Cp]ZrCl2, which undergoes a metathetical reaction with MeMgBr to yield the monomethyl derivative [i-PrP2Cp]Zr(CH3)Cl. The reaction of the Zr(III) complex [i-PrP2Cp]ZrCl2 with excess carbon monoxide results in disproportionation to the Zr(IV) complex, [i-PrP2Cp]ZrCl3, and the Zr(II) compound [i-PrP2Cp]Zr(CO)(2)Cl. This reaction is reversible, and upon removal of CO the starting material, [i-PrP2Cp]ZrCl2 is formed. The preparation of the diamagnetic Nb(III) complex [(P2Cp)-P-R]NbCl2 is achieved by the reaction of NbCl3(DME) with [(P2Cp)-P-R]Li. [(P2Cp)-P-R]NbCl2 complexes react with excess CO to form the CO adducts whose solid-state structures have been determined. The Nb(IV) derivatives [(P2Cp)-P-R]NbCl3 are formed via the reaction of [(P2Cp)-P-R]NbCl2 with PbCl2. These complexes can also be produced when Nb(O)Cl-3(THF)(2) is allowed to react with excess [(P2Cp)-P-R]Li. These Nb(IV) derivatives are ESR active, and their solid-state molecular structures show distorted octahedral geometries around the Nb center. MoCl3(THF)(3) reacts with [(P2Cp)-P-R]Li to generate the corresponding Mo(III) complexes [(P2Cp)-P-R]MoCl2. These compounds are low-spin, paramagnetic complexes as evidenced by their ESR spectra.},
	keywords = {CARBONYL, CHEMISTRY, CONVENIENT, DERIVATIVES, HALOGENO, LINKAGE, {BONDS},
	isbn = {0276-7333},
	url = {<Go to ISI>://000083033500018},
	author = {Fryzuk,Michael D. and Jafarpour, L. and Rettig, S. J.}
}
@article {4232,
	title = {Conjugate Bronsted-Lewis superacids in fluorosulfuric acid - Hammett acidity function and electrical conductivity studies of Ta(V), Nb(V) and Sb(V) Lewis acids},
	journal = {Journal of Fluorine Chemistry},
	volume = {89},
	number = {1},
	year = {1998},
	note = {ISI Document Delivery No.: ZJ736Times Cited: 0Cited Reference Count: 41},
	month = {Apr},
	pages = {117-123},
	type = {Article},
	abstract = {{Conjugate Bronsted-Lewis superacids in fluorosulfuric acid are studied by two techniques. Hammett acidity function studies on HSO3F-Ta(SO3F)(5) in the concentration range of 0-3.4 mol\% of Lewis acid are reported. The conjugate system HSO3F-Ta(SO3F)(5) shows in this range of Lewis acid concentration acidities equal or higher to those of HSO3F-3SO(3)-SbF5, which is commonly assumed to be the strongest conjugate protonic acid. Electrical conductivities of the neat Lewis acids of the type MFn(SO3F)(5-n)},
	keywords = {BEHAVIOR, BIS(FLUOROSULFATE), Bronsted-Lewis, conjugate, CONVENIENT, FLUORIDE, GOLD(III) FLUOROSULFATE, H2SO4-HSO3F, ION, MOLECULAR-STRUCTURES, protonic acid, SYSTEMS, TETRAKIS(FLUOROSULFATO)AURATE(III)},
	isbn = {0022-1139},
	url = {<Go to ISI>://000073247800022},
	author = {Cicha, W. V. and Zhang, D. L. and Aubke, F.}
}
@article {4216,
	title = {The reductive coupling of 2-cyanopyrroles: A study pertaining to the mechanism of formation of porphocyanines},
	journal = {Tetrahedron},
	volume = {54},
	number = {10},
	year = {1998},
	note = {ISI Document Delivery No.: YW979Times Cited: 5Cited Reference Count: 45},
	month = {Mar},
	pages = {2021-2030},
	type = {Article},
	abstract = {2-Cyanopyrrole was found to form (2-pyrrolylmethene)-(2-pyrrolylmethyl)im when treated with lithium aluminum hydride (LAH), followed by a mild work-up. A plausible mechanism of this reductive coupling was inferred from a series of experiments, including Al-27-NMR deuteration experiments, and the reduction of variously substituted cyanopyrroles. The mechanism, a metal chelate mediated dimerization, may be the key to understanding porphocyanine synthesis via the LAH reduction of 1,9-dicyanodipyrromethanes. (C) 1998 Elsevier Science Ltd. All rights reserved.},
	keywords = {CENTERED TEMPLATE REACTIONS, COMPLEX, CONVENIENT, EXPANDED TETRAPYRROLIC MACROCYCLE},
	isbn = {0040-4020},
	url = {<Go to ISI>://000071994000004},
	author = {Bruckner, C. and Xie, L. Y. and Dolphin, D.}
}
