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71.
The reaction of 1,3-dimesitylimidazolium chloride with Ti(NMe(2))(4) results in the 1,3-dimesitylimadazol-2-ylidene complex of Ti(NMe(2))(2)Cl(2)(3); the X-ray crystal structure of 3 evidences short intramolecular Cl...C(carbene) contacts.  相似文献   
72.
A base-stabilized mononuclear aluminum dication has been prepared by extrusion of two triflate anions from a precursor β-diketiminate-supported aluminum bis(triflate) using the tris(2-aminoethyl)amine (tren) ligand.  相似文献   
73.
The first example of a stable oxoborane monomer (LB=O) stabilized by complexation to AlCl3 has been prepared by the reaction of LAlCl2 with BCl3 followed by treatment with H2O in CH2Cl2 (L = [HC(CMe)2(NC6F5)2]). DFT calculations reveal that considerable boron-oxygen double bond character is retained in this complex.  相似文献   
74.
75.
One of the most known elementary inequalities is Bernoulli's inequality. This paper is a complete review on this important inequality.  相似文献   
76.
Summary The hydrazide of 1-naphthylacetic acid forms both bis- and tris-(ligand) high-spin nickel(II) and cobalt(II) complexes possessing an octahedral configuration. The compositions of the complexes are influenced not only by the metal-ligand stoichiometry but also by the nature of the inorganic anion. A physico-chemical investigation showed that the ligand is neutral and bidentate, coordinated through amido-nitrogen and carbonyl oxygen. The compounds were characterized by elemental analysis, magnetic measurements, i.r. and diffuse-reflection spectra and molar conductivity.  相似文献   
77.
78.
A catalytically active aluminum‐based system for Diels–Alder transformations is reported. The system was generated by mixing a β‐diketiminate‐stabilized aluminum bistriflate compound with Na[BArCl4] (ArCl=3,5‐Cl2C6H3). Solid‐state analysis of the catalytic system reveals a unique structure incorporating a two‐dimensional coordination polymer. According to the experimental results obtained from several Diels–Alder transformations, the aluminum‐based system appears to be a more practical and more robust alternative to the recently reported compounds based on carbon and silicon cations.  相似文献   
79.
Aminoboranes, H(2)BNRR', represent the monomeric building blocks from which novel polymeric materials can be constructed via metal-mediated processes. The fundamental capabilities of these compounds to interact with metal centers have been probed through the coordination of H(2)BNCy(2) at 16-electron [CpRu(PR(3))(2)](+) fragments. In contrast to the side-on binding of isoelectronic alkene donors, an alternative mono(σ-BH) mode of aminoborane ligation is established for H(2)BNCy(2), with binding energies only ~8 kcal mol(-1) greater than those for analogous dinitrogen complexes. Variations in ground-state structure and exchange dynamics as a function of the phosphine ancillary ligand set are consistent with chemically significant back-bonding into an orbital of B-H σ* character.  相似文献   
80.
Highly unsaturated mono(N-heterocyclic carbene) Ir(iii) systems have been targeted via ligand abstraction protocols. Hydrogenation of Ir(IPr)(cod)Cl (1a) leads to the formation of the highly reactive (fluxional) trimer [Ir(IPr)(H)(2)Cl](3), while the related IMes system undergoes further C-H bond activation. Chloride abstraction from 1a prior to hydrogenation allows access to sources of the 12-electron [Ir(IPr)(H)(2)](+) fragment, which, in the absence of a suitable donor, dimerizes to give [{Ir(IPr)(H)(μ-H)}(2)](2+).  相似文献   
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