[TcII(NO)(trifluoroacetate)4F]2- - synthesis and reactions
By Balasekaran, S. M.; Hagenbach, A.; Drees, M.; Abram, U.
Published in Dalton Trans.
2017
Abstract
Fluoridotetrakis(trifluoroacetato)nitrosyltechnetate(ii) was prepared by the dissolution of Cs2[Tc(NO)F5] in trifluoroacetic acid and addition of (NBu4)F[middle dot]3H2O. The compound crystallizes as a mixed Cs+/NBu4+ salt in the form of green crystals. Unlike the [Tc(NO)F5]2- salts, the product is soluble in organic solvents and can be used as a precursor for ongoing ligand exchange procedures with organic ligands. The corresponding reactions with triphenylphosphine (PPh3), 1,2-bis(diphenylphosphino)ethane (DPPE) or pyridyldiphenylphosphine (pyPPh2) give technetium(i) complexes of the compositions Cs[Tc(NO)(PPh3)2(CF3COO)2F], [Tc(NO)(DPPE)2(OOCCF3)](PF6) and [Tc(NO)([small kappa]N,P-pyPPh2)([small kappa]P-pyPPh2)(CF3COO)2]. The products were studied spectroscopically and by X-ray diffraction. The 99Tc NMR resonances of the novel Tc(i) nitrosyls appear between -627 and +952 ppm, which is at a remarkably high field and in the range where normally the signals of Tc(iii) compounds are observed.