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Abstract: The first mononuclear copper(II) complexes [N(Dipp)C(NMe2)NC(NMe2)N(SiMe3)]CuCl (Dipp=2,6-iPr2-C6H3) (2) and [N(Ph)C(NMe2)NC(NMe2)N(SiMe3)]2Cu (3) with 1,3,5-triazapentadienyl ligands have been synthesized and structurally characterized by X-ray crystallography and spectroscopic techniques. The X- ray structures of 2 and 3 show that they crystallize in the triclinic system. Trigonal planar structure is observed for the Cu(II) center in 2 and a square-planar environment in 3. The magnetic properties of 2 and 3 have been investigated. [Copyright &y& Elsevier]

The title complex, [Cu(C21H38N5Si)(C18H15P)], was obtained from the one-pot reaction between (Dipp)N(Li)SiMe3 (Dipp = 2,6-diiso-propyl-phen-yl), Me2NCN, CuCl and PPh3. The Cu(I) atom has a distorted trigonal-planar coordination sphere. The tri-aza-penta-dienyl ligand acts as a κ(2)-donor. The N-Cu-N bond angle is 95.88 (14)°. In the tri-aza-penta-dienyl fragment, the C-N bond lengths are in the range 1.328 (5)-1.349 (5) Å, which indicates delocalization of the π-electrons in the NCNCN system.

The title complex, [LiBr(C3H6N2)] n , is the unexpected product of a reaction beteween (Dipp)N(Li)SiMe3 (Dipp = 2,6-diiso-propyl-phen-yl), Me2NCN and CuBr. The compound is a one-dimensional polymer with a step structure derived from the association of inversion dimers, formed by bromido ligands bridging two Li(+) cations, each of which carries a di-methyl-cyanamide ligand. The planar (LiBr)2 unit of the polymer core has a regular rhombic shape [Li-Br-Li 77.55 (16)° and Br-Li-Br 102.45 (16)°]. These (LiBr·NCNMe2)2 dimers represent the repeat unit of a polymer system propagated by additional Br-Li and Li-Br bonds generating an infinite step structure along the a-axis direction.

Treatment of the appropriate lithium or sodium 2,4-N,N'-disubstituted 1,3,5-triazapentadienate [RNC(R')NC(R')N(SiMe(3))M](2) (R = Ph, 2,6-(i)Pr(2)-C(6)H(3)(Dipp) or SiMe(3); R' = NMe(2) or 1-piperidino; M = Li or Na) with one or half equivalent portion of MgBr(2)(THF)(2) in Et(2)O under mild conditions furnishes in good yield the first structurally characterized molecular magnesium 2,4-N,N'-disubstituted 1,3,5-triazapentadienates [DippNC(NMe(2))NC(NMe(2))N(SiMe(3))MgBr](2) (1), [{RNC(R')NC(R')N(SiMe(3))}(2)Mg] (R = Ph, R' = NMe(2) 2; R = Ph, R' = 1-piperidino 3; R = SiMe(3), R' = 1-piperidino 4). The solid-state structure of 1 is dimeric and those of 2, 3, and 4 are monomeric. The ligand backbone NCNCN in 1 adopts a W-shaped configuration, while in 2, 3 and 4 adopts a U-shaped configuration., (© 2011 American Chemical Society)

The title complex, dichlorido[N,N-di-methyl-2-(η(5)-tetra-methyl-cyclo-penta-dien-yl)acetamidinido-κN']titanium(IV), [Ti(C(13)H(20)N(2))Cl(2)], exhibits an unusual ansa-bridged conformation. The cyclo-penta-dienyl ring and the mean plane of the Ti-N=C-C-C fragment form a dihedral angle of 88.08 (11)°.

The title compound, [Cu(3)(C(6)H(18)NSi(2))(C(9)H(24)N(3)Si(2))(2)], is a trinuclear Cu(I) complex. A crystallographic twofold axis passes through one Cu(I) atom and the N atom of the bis-(trimethyl-silyl)amide ligand that bridges between the other two Cu(I) atoms. The Cu-Cu bonds bridged by the guanadinate ligands [2.7913 (9) Å] are slightly longer than the Cu-Cu bond bridged by the bis-(trimethyl-silyl)amide ligand [2.6405 (11) Å].

Addition reaction of ArN(SiMe 3)M (Ar = Ph or 2,6 - (i) Pr 2-C 6H 3 (Dipp); M = Li or Na) to 2 equivalents of alpha-hydrogen-free nitrile RCN (R = dimethylamido) gave the dimeric [M{N(Ar)C(NMe 2)NC(NMe 2)N(SiMe 3)}] 2 ( 1a, Ar = Ph, M = Li; 1b, Ar = Ph, M = Na; 1c, Ar = Dipp, M = Li). 1d was obtained by hydrolysis of 1c at ambient temperature. Treatment of a double ratio of 1a or 1b with anhydrous MCl 2 (M = Mn, Fe, Co) yielded the 1,3,5-triazapentadienato complexes [M{N(Ph)C(NMe 2)NC(NMe 2)N(SiMe 3)} 2] (M = Mn, 2; Fe, 3; Co, 4) and with NiCl 2.6H 2O gave [M{N(Ph)C(NMe 2)NC(NMe 2)N(H)} 2] (M = Ni, 5). Treatment of an equiv of 1c with anhydrous CuCl in situ and in air led to complexes [{N(Dipp)C(NMe 2)NC(NMe 2)N(SiMe 3)}CuPPh 3] 6 and [Cu{N(Dipp)C(NMe 2)NC(NMe 2)N(H)} 2] 7, respectively. 1c, 1d, and 2- 7 were characterized by X-ray crystallography and microanalysis. 1c, 1d, 5, and 6 were well characterized by (1)H, (13)C NMR, 1c by (7)Li, and 6 by (31)P NMR as well. The structural features of these complexes were described in detail.

Treatment of the appropriate sodium beta-diketiminate NaL or NaL' with an equivalent portion of TlCl in thf under mild conditions furnishes in good yield the first structurally characterised thallium beta-diketiminates: the monomeric, orange, crystalline Tl(I) complexes TlL and TlL' [L = {N(SiMe3)C(Ph)}2CH, L' = {N(C6H3Pr(i)(2)-2,6)C(H)}2CPh].