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Bis(trimethylsilyl)amides and -methanides of Yttrium — Molecular Structures of Tris(diethylether-O)lithium-(μ-chloro)-tris[bis(trimethylsilyl)methyl]yttriate, solvent-free Yttrium Tris[bis(trimethylsilyl)amide] as well as the Bis(benzonitrile) Complex The reaction of yttrium(III) chloride with the three-fold molar amount of LiE(SiMe3)2 (E = N, CH) yields the corresponding yttrium derivatives. Yttrium tris-[bis(trimethylsilyl)amide] crystallizes in the space group P3 1c with a = 1 636,3(2), c = 849,3(2) pm, Z = 2. The yttrium atom is surrounded trigonal pyramidal by three nitrogen atoms with Y? N-bond lengths of 222 pm. Benzene molecules are incorporated parallel to the c-axes. The compound with E = CH crystallizes as a (Et2O)3LiCl-adduct in the monoclinic space group P21/n with a = 1 111,8(2), b = 1 865,2(6), c = 2 598,3(9) pm, β = 97,41(3)° and Z = 4. The reaction of yttrium tris[bis(trimethylsilyl)amide] with benzonitrile yields the bis(benzonitrile) complex, which crystallizes in the triclinic space group P1 with a = 1 173,7(2), b = 1 210,3(2), c = 1 912,4(3) pm, α = 94,37(1), β = 103,39(1), γ = 117,24(1)° and Z = 2. The amido ligands are in equatorial, the benzonitrile molecules in axial positions.  相似文献   
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The novel bis(iminophosphorano)methanes CH2[P{NP(S)(OR)2}Ph2]2 (R = Ph (1a), Et (1b)) have been obtained by oxydation of dppm with the corresponding thiophosphorylated azides (RO)2P(S)N3. Deprotonation of 1a,b with KH generates the methanide species KCH[P{NP(S)(OR)2}Ph2]2 (R = Ph (2a), Et (2b)). The ruthenium(II) dimer [{Ru(η6-p-cymene)(μ-Cl)Cl}2] reacts with 2a,b to afford the cationic complexes [Ru(η6-p-cymene)(κ3-C,N,S-CH[P{NP(S)(OR)2}Ph2]2)]+ (R = Ph (3a), Et (3b)), via selective κ3-C,N,S-coordination of the bis(iminophosphorano)methanide anions to ruthenium. The structure of [Ru(η6-p-cymene)(κ3-C,N,S-CH[P{NP(S)(OEt)2}Ph2]2)][PF6] (3b) has been confirmed by single-crystal X-ray crystallography. Deprotonation of complexes 3a,b with NaH leads to the neutral carbene derivatives [Ru(η6-p-cymene)(κ2-C,N-C[P{NP(S)(OR)2}Ph2]2)] (R = Ph (4a), Et (4b)).  相似文献   
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Developing the structures of organic materials that rely on the hydrogen bonding of multifunctional substrates is often complicated due to a competition between various possible motifs. In this context, the illustrative case of the carbamoylcyanonitrosomethanide anion, [ONC(CN)–C(O)NH2], suggests sufficient control over the crystal lattice with a set of supramolecular synthons, which are specific to all the present nitroso, carbamoyl and cyano groups. The structures of the carbamoylcyanonitrosomethanide salts of ethane-1,2-diammonium, C2H10N22+·2C3H2N3O2, (1), piperazine-1,4-diium, C4H12N22+·2C3H2N3O2, (2), butane-1,4-diammonium, C4H14N22+·2C3H2N3O2, (3), and hexane-1,6-diammonium, C6H18N22+·2C3H2N3O2, (4), reveal two- and three-dimensional hydrogen-bonded frameworks governed by a set of site-selective interactions. The strongest N—H…O hydrogen bonds [N…O = 2.6842 (17)–2.8718 (17) Å, mean 2.776 (2) Å] are associated with the polarized ammonium N—H donors and nitroso O-atom acceptors, which sustain invariant motifs in the form of nitroso/ammonium dimers. Subtle structural changes within this series of compounds concern the rupture of some weaker interactions, i.e. mutual hydrogen bonds of the carbamoyl groups in (1)–(3) [N…O = 2.910 (2)–2.9909 (18) Å; mean 2.950 (2) Å] and carbamoyl/nitrile hydrogen bonds in (1), (2) and (4) [N…N = 2.936 (2)–3.003 (3) Å, mean 2.977 (2) Å], providing a gradual evolution of the hydrogen-bonding pattern. A hierarchy of the synthons involving three different groups could be applicable to supramolecular synthesis with polyfunctional methanide species, suggesting also a degree of control over layered and interpenetrated hydrogen-bonded networks.  相似文献   
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Reactions of bis(phosphinimino)methanes H2C(PPh2NR)2 [R = SiMe3 (L1H), Ph (L2H), 2,6‐iPr2‐C6H3 (DIPP) (L3H)] with ZnR2 (R = Me, Et) yielded the corresponding bis(phosphinimino)methanide zinc complexes LZnMe [L2 ( 1 ), L3 ( 2 )] and LZnEt [L1 ( 3 ), L2 ( 4 ), and L3 ( 5 )]. Complexes 1 – 5 were characterized by heteronuclear NMR (1H, 13C, 31P) and IR spectroscopy, elemental analysis, and single‐crystal X‐ray diffraction.  相似文献   
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