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"[Cu(MeCN)4]+, often encountered as its PF6− salt, is a common transition metal nitrile complex. Transition metal nitrile complexes are coordination compounds containing nitrile ligands. Because nitriles are weakly basic, the nitrile ligands in these complexes are often labile. Scope of nitriles Typical nitrile ligands are acetonitrile, propionitrile, and benzonitrile. The structures of [Ru(NH3)5(NCPh)]n+ have been determined for the 2+ and 3+ oxidation states. Upon oxidation the Ru-NH3 distances contract and the Ru-NCPh distances elongate, consistent with amines serving as pure-sigma donor ligands and nitriles functioning as pi-acceptors. Structural comparisons of [Ru(NH3)5(NCPh)]n+ for 2+ and 3+ salts (distance in picometers) Synthesis and reactions Acetonitrile, propionitrile and benzonitrile are also popular solvents. Because nitrile solvents have high dielectric constants, cationic complexes containing a nitrile ligand are often soluble in a solution of that nitrile. Some complexes can be prepared by dissolving an anhydrous metal salt in the nitrile. In other cases, a suspension of the metal is oxidized with a solution of NOBF4 in the nitrile: :Ni + 6 MeCN + 2 NOBF4 → [Ni(MeCN)6](BF4)2 + 2 NO Heteroleptic complexes of molybdenum and tungsten can by synthesized from their respective hexacarbonyl complexes. :M(CO)6 + 4 MeCN + 2 NOBF4 → [M(NO)2(MeCN)4](BF4)2 Portion of the structure of the tetrachlorozincate (ZnCl42−) salt of [Ni(MeCN)6]2+ For the synthesis of some acetonitrile complexes, the nitrile serves as a reductant. This method is illustrated by the conversion of molybdenum pentachloride to the molybdenum(IV) complex: : 2 MoCl5 + 5 CH3CN → 2 MoCl4(CH3CN)2 + ClCH2CN + HCl Reactions Transition metal nitrile complexes are usually employed because the nitrile ligand is labile and relatively chemically inert. Cationic nitrile complexes are however susceptible to nucleophilic attack at carbon. Consequently some nitrile complexes catalyze the hydrolysis of nitriles to give the amides. Fe- and Co- nitrile complexes are intermediates in nitrile hydratase enzymes. N-coordination activates the sp-hybridized carbon center toward attack by nucleophiles, including water. Thus coordination of the nitrile to a cationic metal center is the basis for the catalytic hydration: :M-NCR + H2O → M-O=C(NH2)R :M-O=C(NH2)R + NCR → O=C(NH2)R + M-NCR Examples * Tetrakis(acetonitrile)copper(I) hexafluorophosphate ([Cu(MeCN)4]PF6), a colorless solid that serves as a source of naked "Cu+" * Bis(benzonitrile)palladium dichloride (PdCl2(PhCN)2), an orange solid that serves as a source of "PdCl2" * Hexakis(acetonitrile)nickel(II) tetrafluoroborate ([Ni(MeCN)6](BF4)2), a blue solid that is a source of naked "Ni2+" * Dimolybdenum deca- and octakis(acetonitrile) tetrafluoroborate ([Mo2(MeCN)8/10](BF4)4), a source of "naked" Mo24+. Related Tc24+, Re24+, and Rh24+ complexes are also known. * Tricarbonyltris(propionitrile)molybdenum(0) (Mo(CO)3(C2H5CN)3), a source of "Mo(CO)3". Related Cr and W complexes are known. Complexes of η2-nitrile ligands In some of its complexes, nitriles function as η2-ligands. This bonding mode is more common for complexes of low- valence metals, such as Ni(0). Complexes of η2-nitriles are expected to form as transient intermediates in certain metal-catalyzed reactions of nitriles, such as the Hoesch reaction and the hydrogenation of nitriles. In some cases, η2-nitrile ligands are intermediates that preceded oxidative addition. Structure of Ni(diphosphine)(η2-PhCN) See also * Cyanometalate - coordination compounds containing cyanide ligands (coordinating via C) References Coordination compounds Hexafluorophosphates Tetrafluoroborates "
"Alan Arnold Diamonstein (August 20, 1931 – October 17, 2019) was an American attorney and Democratic Party politician. Diamonstein served in the Virginia House of Delegates from 1968 to 2002, representing parts of Newport News. Diamonstein chose not to run for reelection in 2001, seeking instead the Democratic nomination for lieutenant governor. He came in second to Richmond mayor Tim Kaine, who would go on to win in the general election. Diamonstein was the chair of the Democratic Party of Virginia from 1982 to 1985. References External links * 1931 births 2019 deaths Members of the Virginia House of Delegates Jewish American state legislators in Virginia Virginia Democrats Virginia lawyers Military personnel from Virginia University of Virginia alumni University of Virginia School of Law alumni Politicians from Newport News, Virginia 20th-century American politicians 21st-century American politicians "
"Stink Lake Mountain is a small mountain range located in Central New York Region of New York located in the Town of Ohio in Herkimer County and Town of Morehouse in Hamilton County, northeast of Ohio. Stink Lake is located south of the elevation. References Mountains of Herkimer County, New York Mountains of New York (state) "