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We have studied the influence of nitrogen on the chemical properties of the hydrogenated carbon nitride (a-CN(x):H) film deposited by CH(4)/N(2) dielectric barrier discharge (DBD) plasma. X-ray photoelectron spectroscopy (XPS) indicates that carbon and nitrogen form an unpolarized covalent bond in these C-N(x) materials, and the observed chemical shift in the C 1s and N 1s binding energy is explained with respect to N 1s incorporation. Furthermore, the average nitrogen content (N/C approximately 0.76) in the films was systematically varied by changing the nitrogen partial pressure (CH(4)/N(2) approximately from 5:1 to 1:7) which is well supported by the elemental analysis. Fourier transform infrared (FTIR) absorption spectra exhibit significant changes in different C-N, C identical withN, and NH/OH molecular bands at higher nitrogen concentration in the film. The isonitrile and nitrile groups (-NC and -CN) are increased with the increase of deposition time. In addition, the elemental analysis, proton NMR, and thermolysis mass spectrum show that the composition of the film with the ratio CH(4)/N(2) approximately 1:1 is C, 67.68; H, 9.88; N, 16.53 (in wt %) and that the film is composed of polymers, probably containing linear chains which are cleaved off on heating in vacuum.

The syntheses of novel bulky N-substituted 1,3-benzazaphospholes are presented, together with their reactions with tert-butyllithium and coupling with tBu 2PCl to novel P, P'-hybrid ligands that combine the highly basic and bulky di- tert-butylphosphanyl group with pi-acidic low-coordinated phosphorus. The syntheses start with the preparation of new N-secondary 2-bromoanilines 1 by reduction of N-acyl 2-bromoanilides or more generally by Pd-catalyzed selective monoamination of o-dibromobenzene, followed by Pd-catalyzed C-P coupling with P(OEt) 3 to the respective 2-anilino-phosphonates 2. The next steps are reduction to 2-phosphanylanilines 3 and condensation with Me 2NCH(OMe) 2, which leads via phosphaalkenes 4 to the corresponding N-substituted benzazaphospholes 5. The reaction with tBuLi depends on the steric demand of the N substituent. Methyl, neopentyl-, and mesityl-derivatives were converted to P=C Li species 6 and coupled with tBu 2PCl to novel P=C-P tBu 2 ligands 7, whereas N-adamantyl and N-2,6-diisopropylphenyl-derivatives prefer addition of tBuLi at the PC bond to form dihydroderivatives. The chemical shifts of the low-coordinated phosphorus of 5 and 7 were found to reflect electronic and steric effects of the N substituents. The comparison of the crystal structures of N-neopentyl-1,3-benzazaphospholes 5 and 7 gives evidence of steric repulsion between the adjacent di- tert-butyl and neopentyl groups by the preferred anti orientation of the P- tert-butyl groups and moderate deviations of C2 and P3 of 7b from the ring plane.

A novel linear trinuclear mu-O-bridging 2-phosphinophenolate nickel(II) complex with fac-tris(P(intersection)O- chelates) in the terminal positions and the three oxygen atoms each facing the central nickel(II) cation was synthesized and structurally characterized by X-ray crystallography. To the best of our knowledge, this is the first example of an octahedral Ni(II) tris(P(intersection)O- chelate).

The title compound was obtained from the cyclic diaminogermylene C(2)H(2)[N(CH(2)Bu(t))](2)Ge and cis-[Mo(CO)(4)(NCEt)(2)] and its crystal structure determined revealing structural changes in the coordinated ligand indicative of strong pi-acceptor properties.