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Indian Journal of Chemistry -Section A (IJC-A) >
IJC-A Vol.46A [2007] >
IJC-A Vol.46A(06) [June 2007] >
| Title: | Multinuclear NMR investigation on newly synthesized gold(I) pentafluorophenyl-arylazoimidazole complexes |
| Authors: | Byabartta, Prithwiraj Laguna, Mariano |
| Issue Date: | Jun-2007 |
| Publisher: | CSIR |
| IPC Code: | Int. Cl. ⁸ C07F1/12; G01N24/00 |
| Abstract: | Reaction of [Au(C₆F₅)(tht)] with RaaiR' in dichloromethane yields [Au(C₆F₅)(RaaiR')] [RaaiR' = p-R-C₆H₄-N=N-C₃H₂-NN-1-R', (1-3), abbreviated as N,N'-chelator, where N(imidazole) and N(azo) represent N and N', respectively, R = H, Me, Cl and R' = Me, CH₂CH₃, CH₂Ph]. The maximum molecular peak of [Au(C₆F₅)(MeaaiMe)]¬ is observed at m/z 564.01 in the FAB mass spectrum. IR spectra of the complexes show -C=N- and -N=N- stretching at 1590 and 1370 cm⁻¹ and at 1510, 955, 800 cm⁻¹ due to the presence of pentafluorophenyl ring. The ¹H NMR spectral measurements suggest that methylene group in RaaiEt gives a complex AB multiplet with coupling constant of 7.6 Hz, while in RaaiCH₂Ph, it shows AB type quartets with coupling constant of 7.2 Hz. ¹³C NMR spectrum of the complexes assign the molecular skeleton. In the ¹H-¹H COSY spectrum of the present complexes, absence of any off-diagonal peaks extending from δ = 14.12 ppm and 9.55 ppm confirm no proton on N(1) and N(3) respectively. In the ¹H-¹³C HMQC spectrum, since there are no contours at
δ = 157.12, 160.76, 155.67 ppm and 157.68—160.2 ppm, these may be assigned to the C(2), C(6), C(12) and C(13, 14, 15, 16 and 17) carbon atoms respectively. The solution structure and stereoretentive transformation in each step have been established from ¹H NMR data. The electrochemistry gives the ligand reduction peaks. |
| Page(s): | 937-941 |
| ISSN: | 0376-4710 |
| Source: | IJC-A Vol.46A(06) [June 2007]
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