@article {1113,
	title = {Intramolecular C-H and N-H transfer by ruthenium(II) amidophosphine complexes},
	journal = {Organometallics},
	volume = {24},
	number = {22},
	year = {2005},
	note = {ISI Document Delivery No.: 976PNTimes Cited: 6Cited Reference Count: 51},
	month = {Oct},
	pages = {5440-5454},
	type = {Article},
	abstract = {The formation of ruthenium amidophosphine complexes was accomplished by the addition Of [P2N2]Li-2(Diox) (where P2N2 is PhP(CH2SiMe2NSiMe2CH2)(2)PPh and Diox is 1,4-dioxane) to [RuCl2(cod)](x) to generate [P2N2]Ru(cod), or to RuCl2(PPh3)(3) to generate [P2NNH]Ru(C6H4PPh2) In the former complex, the Ru(II) center is in an octahedral environment perched above the P2N2 macrocycle having two formally anionic amido donors; in the latter complex, there is only one amido ligand with the other as an amine donor where the proton originates from the cyclometalated triphenylphosphine group. Reaction of the tridentate amidophosphine ligand precursor [NPN]Li-2(THF)(2) (where NPN is PhP(CH2SiMe2NPh)(2)) with [RuCl2(cod)](x) results in the formation of two diastereomeric complexes of the formula [NPNH]Ru(eta(3):eta(2)-C8H11), wherein the cyclooctadiene ligand has been deprotonated by the ancillary ligand to generate a cyclooctadienyl unit. These Ru(II) complexes are five-coordinate with a bidentate PN ligand and a dangling amine unit. The diastereomers are in equilibrium, as shown by variable-temperature NMR studies. The fluxional process that interconverts diastereomers involves proton transfer from the dangling amine arm to the amido unit, a process that equilibrates the two ends of the tridentate NPN ligand on the chemical time scale. Deprotonation of the amine arm by MN(SiMe3)(2) generates a series of ruthenate complexes of the formula [M(THF)]([NPN]Ru(eta(3):eta(2)-C8H11)), where M = Li or Na. Addition of Me3SiCl results in the formation of new diastereomers that contain silylated dangling arms, and these diastereomers do not interconvert.},
	keywords = {ACTIVATION, AMIDO COMPLEXES, asymmetric, D6 ML5 COMPLEXES, ENANTIOSELECTIVE HYDROGENATION, EXCHANGE-REACTIONS, HYDROGENATION, KETONES, OPPORTUNITIES NOBEL LECTURE, RU-X BOND, STEREOSELECTIVE HYDROGENATION},
	isbn = {0276-7333},
	url = {<Go to ISI>://000232745700031},
	author = {Fryzuk,Michael D. and Petrella, M. J. and Patrick, B. O.}
}
@article {4548,
	title = {One-electron oxidation of paramagnetic chromium(II) alkyl complexes with alkyl halides: synthesis and structure of five-coordinate chromium(III) complexes},
	journal = {Journal of the Chemical Society-Dalton Transactions},
	number = {2},
	year = {1999},
	note = {ISI Document Delivery No.: 162JPTimes Cited: 18Cited Reference Count: 69},
	month = {Jan},
	pages = {147-154},
	type = {Article},
	abstract = {The reaction of square-planar, high-spin CrR[N(SiMe2CH2PPh2)(2)] (R = Me, CH2SiMe3) with alkyl halides (MeI, CF3CH2I, MeBr, PhCH2Cl) generates one-electron oxidation products Cr(R)X[N(SiMe2CH2PPh2)(2)], unusual examples of five-coordinate chromium(III) complexes. Cr(Me)Br[N(SiMe2CH2PPh2)(2)] and Cr(CH2SiMe3)Cl[N(SiMe2CH2PPh2)(2)] have structurally characterized. Alkylation of the latter complex with LiCH2SiMe3 gave a five-coordinate Cr(III) dialkyl complex Cr(CH2SiMe3)(2)[N(SiMe2CH2PPh2)(2)](2), which was structurally characterized as well. Attempts to isolate sterically unencumbered Cr(III) dialkyl (e.g., dimethyl) complexes resulted in decomposition. Addition of an excess of PhCH2Cl to {[(Ph2PCH2SiMe2)(2)N]Cr}(2)(mu-Cl)(2) resulted in halide-transfer to form CrCl2(TNF)[N(SiMe2CH2PPh2)(2)] in low yield. Reaction of the low-spin CrCp[N(SiMe2CH2PPh2)(2)] complex with PhCH2Cl, however, gave both Cr(Cp)(CH2Ph)[N(SiMe2CH2PPh2)(2)] and Cr(CP)Cl[N(SiMe2CH2CH2PPh2)(2)]. The five five-coordinate Cr(III) alkyl halide complexes do not polymerize ethylene at 60 degrees C and 1 atm; the dialkyl complex Cr(CH2SiMe3)(2)[N(SiMe2CH2PPh2)(2)] does catalyze polyethylene formation but is quickly deactivated. A discussion comparing the structural distortions observed in these five-coordinate high-spin d(3) Cr(III) complexes with those observed in the analogous low-spin d(6) Ir(III) complexes is presented.},
	keywords = {17-ELECTRON, 5-COORDINATE, ATOM TRANSFER-REACTIONS, CHEMISTRY, CRYSTAL-STRUCTURE, D6 ML5 COMPLEXES, NMR-SPECTROSCOPY, ORGANIC HALIDES, POLYMERIZATION, REACTIVITY},
	isbn = {0300-9246},
	url = {<Go to ISI>://000078342700010},
	author = {Fryzuk,Michael D. and Leznoff, D. B. and Rettig, S. J. and Young, V. G.}
}
@article {4263,
	title = {One-electron transformations of paramagnetic cobalt complexes. Synthesis and structure of cobalt(II) amidodiphosphine halide and alkyl complexes and their reaction with alkyl halides},
	journal = {Journal of the American Chemical Society},
	volume = {120},
	number = {39},
	year = {1998},
	note = {ISI Document Delivery No.: 127ZPTimes Cited: 33Cited Reference Count: 106},
	month = {Oct},
	pages = {10126-10135},
	type = {Review},
	abstract = {Complexes of the type CoX[N(SiMe2CH2PPh2)(2)], where X = Cl, Br, or I, can be prepared via reaction of CoX2 with LiN(SiMe2CH2PPh2)(2); these derivatives are tetrahedral high-spin d(7) systems. Reaction of these halide complexes with organolithium, sodium, or potassium reagents generates square-planar, low-spin hydrocarbyl complexes of the formula CoR[N(SiMe2CH2PPh2)(2)] (R = Me, CH2Ph, CH2SiMe3, C5H5). One-electron oxidations have been carried out; only the product of halide abstraction is observed. For example, addition of PhCH2X to the halide derivatives CoX[N(SiMe2CH2PPh2)(2)] generates trivalent, paramagnetic complexes, CoX2[N(SiMe2CH2PPh2)(2)]; these derivatives show variable-temperature magnetic susceptibility data that are consistent with zero-field splitting of the S = 1 state. Addition of methyl bromide or methyl iodide to low-spin CoMe[N(SiMe2CH2PPh2)(2)] results in the formation of the Co(II) halide derivatives CoX[N(SiMe2CH2PPh2)(2)] along with methane and bibenzyl. It is proposed that the Co(III) methyl halide complex CoMe(X) [N(SiMe2CH2PPh2)(2)] is unstable and loses methyl radical homolytically to generate the Co(II) halide derivative; the methyl subsequently reacts with the toluene solvent to produce methane and bibenzyl. Addition of excess benzyl halides has also been found to generate the Co(II) halide complexes initially, followed by a one-electron oxidation to the Co(II) dihalide derivatives. In much of the one-electron chemistry of the Co(II) derivatives incorporating the amidodiphosphine ligand, the decomposition of the putative but unstable Cs(III) alkyl halide derivative CoRX[N(SiMe2CH2PPh2)(2)] is proposed as a recurring event.},
	keywords = {17-ELECTRON, BOND-DISSOCIATION ENERGIES, COORDINATION CHEMISTRY, D6 ML5 COMPLEXES, DERIVATIVES, HIGHER OXIDATION-STATES, KINETICS, LIGAND, ORGANIC HALIDES, RADICAL REACTIONS},
	isbn = {0002-7863},
	url = {<Go to ISI>://000076381000017},
	author = {Fryzuk,Michael D. and Leznoff, D. B. and Thompson, R. C. and Rettig, S. J.}
}
