Neutral pyrazolyl-bridged nickel nitrosyl complexes. Synthesis, structure, and reactivity

Abstract

. Can. J. Chem. 57, 3090 (1979).A series of neutral pyrazolyl-bridged nickel nitrosyl complexes, [LNi(NO)], (where L = pyrazolyl, N2C3H3; 3,5-dimethylpyrazolyl, N,C5H7; or 3,5-di-tert-butylpyrazolyl, N2Cll-HI,), is described. The nickel atoms are susceptible to nucleophilic attack and the reactivity of the dimers with neutral donor ligands is reported. In addition to the dimeric molecules a novel trimetallic nickel compound [(ON)Ni(N2C5H7)2]2Ni has also been isolated. Introduction In our continuing study of pyrazolyl-based ligands (1, 2) our attention has recently been focused on a series of pyrazolyl metal nitrosyl compounds containing bridging bidentate pyrazolyl moieties. The ligating properties of bridging pyrazolyl groups have been reviewed by Trofimenko (3) and recent reports reflecting the current interest in this type of bridging

Transition metal complexes with pyrazole-derived ligands. XI. [Zn(μ-L)(HL)(OAc)]2(HLis 4-acetyl-3-amino-5-methylpyrazole)

“…In the free and coordinated HL ligand, this distance ranges from 1.373 (5) to 1.385 (2) A Ê . It is interesting to compare this result with the structures of [Zn 2 (dmpz) 4 (Hdmpz) 2 ] (Ehlert et al, 1990; Hdmpz is 3,5-dimethylpyrazole) and [Ni(NO) 2 (dmpz) 2 ] (Chong et al, 1979). In the former compound, the NÐN distances are 1.396 (5) and 1.375 (4) A Ê in the bidentate bridging and monodentate terminal ligands, respectively.…”

Trigonal‐Bipyramidal Lanthanoid Complexes with Interstitial Oxygen Atoms

“…The nitrogen atoms of the terminal q2-dimethylpyrazoly1 ligands, which exhibit Ln-N distances of 227. 5 …”

N2O Formation via Reductive Disproportionation of NO by Mononuclear Copper Complexes: A Mechanistic DFT Study

“…Crystal structures of dinitrosyl complexes as in 4 and 5 are reported for several first-row transition metals, namely, for V, Cr, , Mn, , Fe, − and Co. , While especially dinitrosyl iron complexes (DNIC) are very broadly investigated, − this list lacks the late transition metals Ni and Cu. In that regard, it is particularly interesting to see that, for the same ligand, Fe and Co both form dinitrosyl complexes, while Ni only forms a mononitrosyl complex …”

“…In that regard, it is particularly interesting to see that, for the same ligand, Fe and Co both form dinitrosyl complexes, 59 while Ni only forms a mononitrosyl complex. 66 While no crystal structure containing an O−N−N−O unit is reported for copper, they exist for several other transition metals (all formally classified as hyponitrite, ONNO 2− ): A cis− O−N−N−O unit coordinating with both of its oxygen atoms (structurally analogous to 9) is dominant for electron-rich Ni 18,67,68 and Pt 68,69 complexes. A cis−O−N−N−O unit coordinating via both nitrogen atoms has been reported to bridge two Ru centers.…”