Structural, spectroscopic and catalytic properties of water-soluble hydride rhodium complexes [RhH(Rtpa +I −) 4]H 2O (R=Me, Et)

Abstract

New rhodium(I) hydrido complexes [RhH(mtpa +I −) 4]·H 2O ( 1) and [RhH(etpa +I −) 4]·H 2O ( 2) (where mtpa +I −=1-methyl-1-azonia-3,5-diaza-7-phosphatricyclo[3.3.1.1 3,7]decane iodide, etpa +I −=1-ethyl-1-azonia-3,5-diaza-7-phosphatricyclo[3.3.1.1 3,7]decane iodide) have been synthesized and characterized using 1H, 31P NMR and IR spectra and X-ray crystallography. Both complexes have the trigonal-bipyramidal structure. The 1H NMR spectra indicate that in solutions the complexes have fluxional properties. The compounds are very stable in water under neutral atmosphere. They are efficient catalysts of hydrogenation of CC bonds in two-phase catalytic systems.