Gold-dppm-Arylazoimidazole Complexes: Synthesis, Spectra, and Redox Study

Abstract

[Ag(tht)(OTf)]-assisted reaction produces [AuIII(dppm)(tht)2](OSO2CF3)2, reacts with RaaiR′ in dichloromethane medium followed by ligand addition, and leads to [AuIII(dppm)(RaaiR′)](OTf)2(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′, resp.; R = H (a), Me (b), Cl (c) and R′= Me (1), CH2CH3(2), CH2Ph (3), dppm is diphenylphosphinomethane, OSO2CF3 is the triflate anion, and tht is tetrahydrothiophen). Ir spectra of the complexes show –C=N– and –N=N– stretching near at 1590 and 1370 cm−1 and near at 1100, 755, 695, 545, and 505 cm−1 due to the presence of dppm. The H1 NMR spectral measurements suggest that methylene, –CH2–, in RaaiEt gives a complex AB type multiplet while in RaaiCH2Ph it shows AB type quartets. Electrochemistry assigns ligand reduction.

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Copyright

Copyright © 2010 Prithwiraj Byabartta. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.