1,720,994 research outputs found
Correlation of nitrosyl (NO) stretching frequencies with coordination modes in metal complexes of C-nitroso compounds
No full textIt is shown that the previous use of IR spectroscopy for detn. of the co-ordination mode of p-nitrosodimethylaniline (I) is generally unreliable owing to a faulty assignment of the NO stretching frequency for I itself
Nitrogen-oxygen bond length/stretching frequency relationships in C-nitroso compounds and their coordination complexes
No full textThe mode of coordination of monomeric C-nitroso compds. to metals is discussed. In contrast to previous studies it is proposed that an understanding of the ν(N-O)/r(N-O) and r(C-N)/r(N-O) relationships in the noncoordinated nitroso compds. is of primary importance for assessment of the coordination mode. Both ν(N-O)/r(N-O) and r(C-N)/r(N-O) have linear interrelationships in C-nitroso compds. and the coordination compds. of RNO have the same ν(N-O)/r(N-O) relationship as the noncoordinated monomers. Previous correlations of Δν(N-O) with coordination mode are therefore correlations of r(N-O) with coordination mode. σ-N and σ-O complexes of arom. RNO conform to the same r(C-N)/r(N-O) equation (within a very small error) as the noncoordinated monomers. The extent of deviation from the r(C-N)/r(N-O) relationship for complexes of aliph. RNO is of a similar order of magnitude to that which occurs when C-nitroso monomers form the trans dimer. The coordination mode of aliph. RNO is, with one exception, σ-N. Nitrosobenzene has a variety of coordination modes to transition metals but does not display σ-O coordination. p-Nitrosodimethylaniline undergoes σ-O coordination to d10 metals
Preparative and spectroscopic studies of (PtCl3(4-XC6H4NO))-K+ complexes
No full textσN-Coordinated compds. [PtCl3(4-X-C6H4NO)]-K+ were prepd. and studied by 13C NMR spectroscopy and by variable temp. 1H NMR spectroscopy. The anomalous behavior of the NO group on the 13C chem. shifts is modified by coordination but where X = NMe2 or OCH3 the free energy barriers to rotation of the NO group detd. by 1H NMR studies are closely similar to those of the free ligands. Restricted rotation of the NMe2 group was also studied in [PtCl3(2-CH3-4-NMe2-C6H3NO)]-K+
Coordination complexes of dimethyltin dichloride with C-nitroso compounds
No full textCoordination complexes of five nitroanilines with dimethyltin dichloride have been prepd. and studied by 13C, 15N and 119Sn solid state NMR spectroscopy and by Moessbauer spectroscopy. The 13C resonances of the CH3-Sn groups, the 119Sn resonances and the Moessbauer quadrupole splitting values permit assignment of the two classes of coordination complexes, i.e., 1:1 pentacoordinate and 1:2 octahedral complexes. The C-NO resonances decrease on coordination. The 15N resonances demonstrate that coordination is accompanied by an enhancement of the quinonoid contribution in the ligand itself
Solid state studies of some nitrosoaromatic iron carbonyls
No full textMoessbauer spectroscopic studies of a tricarbonyl(nitrosobenzene)iron compd. and two dicarbonyl(nitrosobenzene)triphenylphosphineiron compds. showed that these compds. possess similar structures and are dimeric in character. Solid state 13C NMR spectroscopy shows that although in such compds. the NO bond length approaches that characteristic of a single bond, the large ipso chem. shift of the NO group is only slightly diminished. Other consequences of coordination for the structure of the C-nitroso ligand are also discussed
Synthesis of Novel Nitroso-Fulleropyrrolidines
Full text linkNovel fulleropyrrolidines I [R1 = Me, Ph; R2 = O2N, H2N, ON, 4-O2NC6H4O(CH2)12O, 4-H2NC6H4O(CH2)12O, 4-ONC6H4O(CH2)12O], contg. nitro, amino, or nitroso groups directly on the Ph ring or spaced by a long chain from the fulleropyrrolidine moiety, were synthesized and characterized
Nitrosoalkenes and their coordination compounds with palladium chloride
No full textTwo nitrosodithiofulvenes and a nitrosodiselenafulvene formed insol. coordination compds. with Pd chloride, these being the 1st reported coordination compds. of nitrosoalkenes. PdCl2.RNO and PdCl2.(RNO)2 were formed. Variable temp. NMR studies of the nitrosoalkenes demonstrate that the free energy barrier to rotation about the bond is low, values being in the range 58-93 kJ mol-1
- …
