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Nitric oxide (NO) is a key signaling molecule in health and disease. While nitrite acts as a reservoir of NO activity, mechanisms for NO release require further understanding. A series of electronically varied β-diketiminatocopper(II) nitrite complexes [Cu(II)](κ(2)-O(2)N) react with a range of electronically tuned triarylphosphines PAr(Z)(3) that release NO with the formation of O=PAr(Z)(3). Second-order rate constants are largest for electron-poor copper(II) nitrite and electron-rich phosphine pairs. Computational analysis reveals a transition-state structure energetically matched with experimentally determined activation barriers. The production of NO follows a pathway that involves nitrite isomerization at Cu(II) from κ(2)-O(2)N to κ(1)-NO(2) followed by O-atom transfer (OAT) to form O=PAr(Z)(3) and [Cu(I)]-NO that releases NO upon PAr(Z)(3) binding at Cu(I) to form [Cu(I)]-PAr(Z)(3). These findings illustrate important mechanistic considerations involved in NO formation from nitrite via OAT.

S-Nitrosothiols RSNO represent circulating reservoirs of nitric oxide activity in the plasma and play intricate roles in protein function control in health and disease. While nitric oxide has been shown to reductively nitrosylate copper(II) centers to form copper(I) complexes and ENO species (E = R(2)N, RO), well-characterized examples of the reverse reaction are rare. Employing the copper(I) β-diketiminate [Me(2)NN]Cu, we illustrate a clear example in which an RS-NO bond is cleaved to release NO(gas) with formation of a discrete copper(II) thiolate. The addition of Ph(3)CSNO to [Me(2)NN]Cu generates the three-coordinate copper(II) thiolate [Me(2)NN]CuSCPh(3), which is unstable toward free NO.

A family of new 1D, 2D, and 3D coordination networks based on metal-pyridylphosphonates have been synthesized under hydro(solvo)thermal conditions. Zn(3-pyridylphosphonate)(bromide), 1, adopts a 1D ladder structure, while Co(4-pyridylphosphonate)(H(2)O)(3), 2, adopts a 2D grid structure. [Cu(2)(4-pyridylphosphonate)(2)]-2H(2)O, 3, [Cd(3-pyridylphosphonate)(2)]-DMSO, 4, Cd(4-pyridylphosphonate)(2), 5, and Cd(ethyl 4-pyridylphosphonate)(2), 6, all adopt 3D framework structures. While 3 possesses open channels that are occupied by water molecules, 4 exhibits cavities that accommodate DMSO guest molecules. The present work demonstrates that interesting open frameworks can be readily synthesized on the basis of metal pyridylphosphonates. Crystal data for 1: monoclinic space group C2/c; a = 15.267(4), b = 11.903(2), c = 10.380(2) A; beta = 98.68(2) degrees; Z = 8. Crystal data for 2: monoclinic space group P2(1)/c; a = 9.634(12), b = 7.611(9), c = 11.901(1) A; beta = 97.830(2) degrees; Z = 4. Crystal data for 3: triclinic spacegroup P one macro; a = 7.464(8), b = 9.203(1), c = 11.602(2) A; alpha = 100.289(1) degrees; beta = 104.532(1) degrees, gamma = 94.569(1) degrees; Z = 2. Crystal data for 4: tetragonal space group I4(1)/a; a = 15.114(2), b = 15.114(2), c = 13.128(3) A; Z = 8. Crystal data for 5: monoclinic space group P2(1)/c; a = 8.344(2), b = 10.589(2), c = 14.384(3) A; beta = 91.77(3) degrees; Z = 4. Crystal data for 6: monoclinic space group P2(1)/n; a = 5.606(1), b = 11.198(1), c = 14.176(2) A; beta = 94.518(1) degrees; Z = 2.

S-Nitrosothiols undergo reversible transnitrosation reactions at tris(pyrazolyl)boratozinc thiolates (iPr2)TpZn-SR. These zinc thiolates are unreactive toward anaerobic NO but rapidly react with NO in the presence of O(2) or anaerobically with NO(2) to release the S-nitrosothiol RSNO with formation of the corresponding zinc nitrate.

beta-Diketiminato Cu(I)-lutidine complexes [RMeNN]Cu(2,4-lutidine) (R = Me (4a), (i)Pr (4b)) were prepared in high yield from Tl[RMeNN] and [CuBr(2,4-lutidine)(2)](2). Both 4a and 4b reversibly dissociate lutidine base in toluene to give [RMeNN]Cu(toluene) solvento complexes. A related base-free dicopper species [[Me(2)NN]Cu](2) (6) bridged via eta(2)-binding of opposing N-aryl rings could be isolated by the addition of Tl[Me(2)NN] to CuBr. The lutidine precursors serve as precatalysts for the aziridination of alkenes with PhI=NTs. Styrene, beta-methylstyrene, and cyclooctene gave the highest yields (59-96%) with a low olefin to PhI=NTs ratio (3:1) and 5 mol % catalyst loading.

beta-Diketiminato Cu(I)-lutidine complexes [RMeNN]Cu(2,4-lutidine) (R = Me (4a), (i)Pr (4b)) were prepared in high yield from Tl[RMeNN] and [CuBr(2,4-lutidine)(2)](2). Both 4a and 4b reversibly dissociate lutidine base in toluene to give [RMeNN]Cu(toluene) solvento complexes. A related base-free dicopper species [[Me(2)NN]Cu](2) (6) bridged via eta(2)-binding of opposing N-aryl rings could be isolated by the addition of Tl[Me(2)NN] to CuBr. The lutidine precursors serve as precatalysts for the aziridination of alkenes with PhI=NTs. Styrene, beta-methylstyrene, and cyclooctene gave the highest yields (59-96%) with a low olefin to PhI=NTs ratio (3:1) and 5 mol % catalyst loading.