@article {2610,
	title = {HL2[P(1,2-O(2)C(6)H4)(3)] (L = DMSO or DMF): A Convenient Proton Source with a Weakly Basic Phosphorus(V) Anion},
	journal = {Organometallics},
	volume = {28},
	number = {15},
	year = {2009},
	note = {ISI Document Delivery No.: 476PYTimes Cited: 0Cited Reference Count: 114Siu, Paul W. Gates, Derek P.},
	month = {Aug},
	pages = {4491-4499},
	type = {Review},
	abstract = {Treating phosphorus pentachloride with catechol (3 equiv) followed by the addition of dimethylsulfoxide (DMSO) or dimethylformamide (DMF) affords isolable bronsted acids of tris- (o-phenylenedioxy)phosphate anion, [p(1,2-O2C6H4)(3)](-). Specifically. H(DMSO)(2)[P(1,2-O2C6H4)(3)] and H(DMF)(2)[P(1,2-O2C6H4)(3)] have been isolated as crystalline solids. The downfield shifts of the acidic proton in their H-1 NMR spectra are consistent with its expected high acidity. The molecular structures of H(DMSO)(2)[P(1,2-O2C6H4)(3)] and H(DMF)(2)[P(1,2-O2C6H4)(3)] reveal that the protons in each are O-bound by either DMSO (x2) or DMF (x2). The N-H stretching frequency for the Oct(3)NH[P(1,2-O2C6H4)(3)] ((V) over bar (N-H) =3129 cm(-1)) is identical to that observed for trioctylammonium tetrafluoroborate ((v) over bar (N-H) = 3129 cm(-1)), suggesting that the basicity of these two weakly coordinating anions is similar. A preliminary investigation of the effectiveness of H(DMF)(2)[p(1,2-O2C6H4] in the protonolysis of metal-alkyl bonds was undertaken. Treating (dppe) pdMe(2) [dppe = 1,2-bis(diphenylphosphino)ethane] with H(DMF)(2)[P(1,2-O2C6H4)(3)] affords either [(dppe)pd(NCMe)Me][P(1,2-O2C6H4)(3) (1:1 ratio) or [(dppe)pd(NCMe)(2)(][P(1,2-O2C6H4)(3)](2) (1:2 ratio), both of which are structurally characterized.},
	keywords = {ALTERNATING COPOLYMERIZATION, ANIONS, CARBON-MONOXIDE, COORDINATING ANIONS, CRYSTAL-STRUCTURE, DIMETHYL-SULFOXIDE, MIGRATORY INSERTION, MOLECULAR-STRUCTURE, OLEFIN, PALLADIUM(II) COMPLEXES, POLYMERIZATION, SUPERWEAK},
	isbn = {0276-7333},
	url = {<Go to ISI>://000268455900036},
	author = {Siu, P. W. and Gates, D. P.}
}
@article {2627,
	title = {Noninnocent Behavior of Ancillary Ligands: Apparent Trans Coupling of a Saturated N-Heterocyclic Carbene Unit with an Ethyl Ligand Mediated by Nickel},
	journal = {Journal of the American Chemical Society},
	volume = {131},
	number = {30},
	year = {2009},
	note = {ISI Document Delivery No.: 479FFTimes Cited: 6Cited Reference Count: 26Steinke, Tobias Shaw, Bryan K. Jong, Howard Patrick, Brian O. Fryzuk, Michael D. Green, Jennifer C.},
	month = {Aug},
	pages = {10461-10466},
	type = {Article},
	abstract = {Oxidative addition of the tridentate N-heterocyclic carbene (NHC) diphosphine ligand precursor ([PCP]H)PF6 (1) {[PCP] = o-(Pr2PC6H4)-Pr-i(NC3H4N)o-(C6H4PPr2)-Pr-i} to Ni(COD)(2) results in the formation of the nickel(II) hydride complex ([PCP]NiH)PF6 (2). This hydride undergoes a rapid reaction with ethylene to generate a nickel(O) complex in which an ethyl group has been transferred to the carbene carbon of the original NHC-diphosphine ligand. If the first intermediate is the anticipated square-planar nickel(II) ethyl species, then the formation of the product would require a process that involves a trans C-C coupling of the NHC carbon and a presumed Ni-ethyl intermediate. Deuterium-labeling studies provide evidence for migratory insertion of the added ethylene into the Ni-H bond rather than into the Ni-catene linkage; this is based on the observed deuterium scrambling, which requires reversible P-elimination, alkene rotation, and hydride readdition. However, density functional theory studies suggest that a key intermediate is an agostic ethyl species that has the Ni-C bond cis to the NHC unit. A possible transition state containing two cis-disposed carbon moieties was also identified. Such a process represents a new pathway for catalyst deactivation involving NHC-based metal complexes.},
	keywords = {ACTIVATION, CHEMISTRY, COMPLEXES, MECHANISM, MIGRATORY INSERTION, NHC, ORGANOMETALLIC CATALYSIS, palladium, REDUCTIVE ELIMINATION, ruthenium},
	isbn = {0002-7863},
	url = {<Go to ISI>://000268644400040},
	author = {Steinke, T. and Shaw, B. K. and Jong, H. and Patrick, B. O. and Fryzuk,Michael D. and Green, J. C.}
}
@article {1062,
	title = {Distinctive properties of Cp {\textquoteright} M(NO)(alkyl)(2) (M = MO, W) complexes},
	journal = {Organometallics},
	volume = {24},
	number = {17},
	year = {2005},
	note = {ISI Document Delivery No.: 953ZRTimes Cited: 16Cited Reference Count: 40},
	month = {Aug},
	pages = {4088-4098},
	type = {Review},
	abstract = {This account summarizes our work with the title complexes, which are rare examples of electronically and coordinatively unsaturated transition-metal alkyls that can be isolated under ambient conditions. It first outlines the synthetic methods employed for the preparation of these compounds and then presents their distinctive physical properties. It then classifies the characteristic chemical properties of these complexes in terms of the reactivity being either metal or ligand based, and specific examples of particular transformations are illustrated with reference to the most studied systems.},
	keywords = {CARBON BONDS, CP{\textquoteright}M(NO)R2, INTERMOLECULAR ACTIVATION, MIGRATORY INSERTION, MOLYBDENUM, NITRIC-OXIDE, ORGANOMETALLIC NITROSYL CHEMISTRY, {C-H BONDS},
	isbn = {0276-7333},
	url = {<Go to ISI>://000231124400002},
	author = {Blackmore, I. J. and Jin, X. and Legzdins,Peter}
}
@article {1263,
	title = {Synthesis and reactivity of zirconium and hafnium complexes incorporating chelating diamido-N-heterocyclic-carbene ligands},
	journal = {Journal of Organometallic Chemistry},
	volume = {690},
	number = {24-25},
	year = {2005},
	note = {ISI Document Delivery No.: 994VFTimes Cited: 36Cited Reference Count: 51},
	month = {Dec},
	pages = {5788-5803},
	type = {Article},
	abstract = {Early transition metal complexes employing a diamido N-heterocyclic carbene (NHC) ligand set (denoted [NCN]) render the centrally disposed NHC moiety stable to dissociation. Aminolysis reactions with the mesityl-substituted ligand precursor ((Mes)[NCN]H-2) and M(NMe2)(4) (M = Zr, Hf) provide bis(amido)-NHC-metal complexes that can be further converted to chloro and alkyl derivatives. Activation of (Mes)[NCN]M(CH3)(2) with [Ph3C][B(C6F5)(4)] yields {(Mes)[NCN]MCH3} {B(C6F5)(4)}, which is surprisingly inactive for the polymerization of 1-hexene. The zirconium cation did, however, show moderate ability to catalytically polymerize ethylene. The hafnium dialkyls are thermally stable with the exception of the diethyl complex, (Mes)[NCN]Hf(CH2CH3)(2), which undergoes P-hydrogen transfer and subsequent C-H bond activation with an ortho-methyl substituent on the mesityl group. The hafnium dialkyl complexes also insert carbon monoxide and substituted isocyanides to yield eta(2)-acyls and eta(2)-iminoacyls, respectively. In some circumstances, further C-C bond coupling occurs to yield enediolates and eneamidolate metallocycles. The molecular structures of (Mes)[NCN]Hf(CH2CHMe2)(2), (Mes)[NCN]Hf(eta(2)-(2,6-Me2C6H3NCCH3)(CH3), (Mes)[NCN]Hf(eta(2)-(2,6-Me2C6H3NCCH3)(2), (Mes)[NCN]Hf(OC(CH3)=C(CH3)NXy), and [(Mes)[NCN]Hf(OC(Bu-i)=C(Bu-i)O)](2) are included. (c) 2005 Elsevier B.V. All rights reserved.},
	keywords = {AMIDO, CARBON-MONOXIDE, CHEMISTRY, DONORS, ETA-2-IMINOACYL, hafnium, LIVING POLYMERIZATION, MIGRATORY INSERTION, N-heterocyclic carbene, OLEFIN, POLYMERIZATION, PROPERTIES, SPECTROSCOPIC, STABLE CARBENES, STRUCTURAL-CHARACTERIZATION, tridentate ligand, ZIRCONIUM, ZIRCONOCENE COMPLEXES},
	isbn = {0022-328X},
	url = {<Go to ISI>://000234058600046},
	author = {Spencer, L. P. and Fryzuk,Michael D.}
}
@article {5076,
	title = {Reaction of [P2N2]Ta=CH2(Me) with ethylene: Synthesis of [P2N2]Ta(C2H4)Et, a neutral species with a beta-agostic ethyl group in equilibrium with an alpha-agostic ethyl group ([P2N2] = PhP(CH2SiMe2NSiMe2CH2)(2)PPh)},
	journal = {Journal of the American Chemical Society},
	volume = {123},
	number = {8},
	year = {2001},
	note = {ISI Document Delivery No.: 405LXTimes Cited: 26Cited Reference Count: 65},
	month = {Feb},
	pages = {1602-1612},
	type = {Article},
	abstract = {The photolysis of [P2N2]TaMe3 ([P2N2] = PhP(CH2SiMe2NSiMe2CH2)(2)PPh) produces [P2N2]Ta=CH2(Me) as the major product. The thermally unstable methylidene complex decomposes in solution in the absence of trapping agents to unidentified products. However, in the presence of ethylene [P2N2]Ta=CH2(Me) is slowly converted to [P2N2]Ta(C2H4)Et, with [P2N2]Ta(C2H4)Me observed as a minor product. A mechanistic study suggests that the formation of [P2N2]Ta(C2H4)Et results from the trapping of [P2N2]TaEt, formed by the migratory insertion of the methylene moiety into the tantalum-methyl bond. The minor product, [P2N2]Ta(C2H4)Me, forms from the decomposition of a tantalacyclobutane resulting from the addition of ethylene to [P2N2]Ta=CH2(Me) and is accompanied by the production of an equivalent of propylene. Pure [P2N2]Ta(C2H4)Et can be synthesized by hydrogenation of [P2N2]TaMe3 in the presence of PMe3, followed by the reaction bf ethylene with the resulting trihydride. Crystallographic and NMR data indicate the presence of a beta -agostic interaction between the ethyl group and tantalum center in [P2N2]Ta(C2H4)Et. Partially deuterated analogues of [P2N2]Ta(C2H4)Et show a large isotopic perturbation of resonance for both the beta -protons and the alpha -protons of the ethyl group, indicative of an equilibrium between a beta -agostic and an a-agostic interaction for the ethyl group in solution. An EXSY spectrum demonstrates that an additional fluxional process occurs that exchanges all of the H-1 environments of the ethyl and ethylene ligands. The mechanism of this exchange is believed to involve the direct transfer of the beta -agostic hydrogen atom from the ethyl group to the ethylene ligand, via the so-called beta -hydrogen transfer process.},
	keywords = {ALKYL ALKENE, C-H, CHAIN PROPAGATION, COMPLEXES, METAL-CARBON BONDS, MIGRATORY INSERTION, MOLECULAR-STRUCTURES, NUCLEAR-MAGNETIC-RESONANCE, OLEFIN, POLYMERIZATION, RAY CRYSTAL-STRUCTURE, TRANSITION-METALS},
	isbn = {0002-7863},
	url = {<Go to ISI>://000167162100008},
	author = {Fryzuk,Michael D. and Johnson, S. A. and Rettig, S. J.}
}
@article {3419,
	title = {NITROSYL N-O BOND-CLEAVAGE DURING REACTIONS OF ORGANOMETALLIC NITROSYL COMPLEXES OF THE GROUP-6 ELEMENTS},
	journal = {Comments on Inorganic Chemistry},
	volume = {17},
	number = {4},
	year = {1995},
	note = {ISI Document Delivery No.: RH843Times Cited: 11Cited Reference Count: 44Part A},
	pages = {239-254},
	type = {Article},
	abstract = {The nitrosyl ligands in organotransition-metal nitrosyl complexes usually stay intact during chemical transformations of these complexes. However, our continuing study of the characteristic reactivity of Group 6 organometallic nitrosyl complexes has recently revealed a number of new product complexes which result from N-O bond cleavage of the nitrosyl groups in the reactants. The various reactions and reaction conditions during which these complexes undergo facile nitrosyl N-O bond dissociation are summarized, and mechanistic ideas as to why these bond cleavages occur are also presented.},
	keywords = {(ETA-5-C5ME5)RU(NO), ACTIVATION, COORDINATED NITRIC-OXIDE, COORDINATIVELY UNSATURATED BRIDGING, GAS-PHASE, GROUP 6, LIGANDS, MIGRATORY INSERTION, MOLYBDENUM, NITROSYL, NITROSYL BOND CLEAVAGE, OXIDATIVE ADDITION-REACTIONS, OXO COMPLEXES, TUNGSTEN},
	isbn = {0260-3594},
	url = {<Go to ISI>://A1995RH84300003},
	author = {Legzdins,Peter and Young, M. A.}
}
@article {2778,
	title = {REACTIVITY OF THE LEWIS-ACIDS CP-ASTERISK-M(NO)(CH2CME3)CL [M = MO, W] AND RELATED COMPLEXES},
	journal = {Organometallics},
	volume = {12},
	number = {7},
	year = {1993},
	note = {ISI Document Delivery No.: LU682Times Cited: 26Cited Reference Count: 43},
	month = {Jul},
	pages = {2714-2725},
	type = {Article},
	abstract = {{Treatments of Cp*M(NO)Cl2 [Cp* = eta5-C5Me5; M = Mo, W] with 0.5 equiv of (Me3CCH2)2Mg.X(dioxane) in THF at low temperatures affords the monoalkylated complexes, Cp*M(NO)(CH2CMe3)Cl (1, 1{\textquoteright}). Exposure to a second 0.5 equiv of (Me3CCH2)2Mg.X(dioxane) at higher temperatures produces the dialkyl complexes, Cp*M(NO)(CH2CMe3)2 (2,2{\textquoteright}). Utilizing the two series of Cp*M(NO)Cl2, Cp*M(NO)(CH2CMe3)Cl and Cp*M(NO)(CH2CMe3)2 complexes, the relative electron deficiencies in these 16-electron complexes can be assessed spectroscopically and electrochemically. Without exception, the Mo complexes are the stronger Lewis acids. Also, the mononeopentyl derivatives for both metals are more reactive toward a variety of substrates than are their bis(neopentyl) analogues. Complexes 1 and 1{\textquoteright} serve as precursors to mixed alkyl and alkyl aryl complexes (3, 3{\textquoteright}, 4, 4{\textquoteright}) and yield metal-centered adducts with PMe3 and pyridine (5, 5{\textquoteright}, 6, 6{\textquoteright}). CO and CNCMe3 readily insert into the M-C bonds of 1 and 1{\textquoteright}. The insertion products, Cp*M(NO)(C{E}CH2CMe3)Cl (7, 7{\textquoteright}},
	keywords = {ALKYL, C-H, CARBONYLATION, CONVERSION, DERIVATIVES, H ACTIVATION REACTIONS, MIGRATORY INSERTION, MOLYBDENUM, ORGANOMETALLIC NITROSYL CHEMISTRY, TUNGSTEN},
	isbn = {0276-7333},
	url = {<Go to ISI>://A1993LU68200046},
	author = {Debad, J. D. and Legzdins,Peter and Rettig, S. J. and Veltheer, J. E.}
}
