The dual role of cis-[RuCl2(dmso)4] in the synthesis of new water-soluble Ru(II)–phosphane complexes and in the catalysis of redox isomerization of allylic alcohols in aqueous–organic biphasic systems

New air-stable, water-soluble Ru(II)–phosphane complexes were synthesized in high purity by the reaction of cis-[RuCl2(dmso)4] with 2 equivalents of 1,3,5-triaza-7-phosphaadamantane (pta) and its N-methyl and N-benzyl derivatives (pta-Me and pta-Bn, respectively). All new complexes were characterized by elementary analysis and spectroscopic methods (NMR, ESI-MS) and the molecular structures of cis-cis-trans-[RuCl2(dmso)2(pta)2], cis-cis-trans-[RuCl2(dmso)2(pta-H)2]Cl2 (obtained in acidic solutions) and that of cis-cis-trans-[RuCl2(dmso)2(pta-Me)2](CF3SO3)2 were determined by single crystal X-ray diffraction.Under mild conditions, cis-[RuCl2(dmso)4] actively catalyzed the transformation of allylic alcohols into the corresponding ketones with 100% selectivity while in the same reaction the new Ru(II)–pta complexes showed moderate activity and selectivity.

New air-stable, water-soluble cis-cis-trans-[RuCl2(dmso)2L2] complexes were synthesized by the reaction of cis-[RuCl2(dmso)4] with 2 equivalents of triazaphosphaadamantanes (L). These complexes and that of cis-[RuCl2(dmso)4] act as catalysts for isomerization of 1-octen-3-ol in the presence of HCOONa.Figure optionsDownload as PowerPoint slideHighlights
► cis-[RuCl2(dmso)4] (1) was used as a water-soluble Ru(II) source for synthesis.
► New water-soluble Ru(II)-complexes were obtained from 1 and phosphatriazaadamantanes (L).
► Single crystal X-ray structures evidenced cis-cis-trans-[RuCl2(dmso)2L2] geometries.
► 1 and the new complexes actively catalyzed the isomerization of allylic alcohols.