Base-Promoted Hydroalkylation Reactions of 1,3,5-Me₃C₆H₃, <i>p</i>-MeC₆H₄CHMe₂, C₆Me₆, <i>p</i>-MeC₆H₄Me, and MeC₆H₅ Ligands Coordinated to Ruthenium(II)

Abstract

The [(η6-arene)RuCl2]2 (arene = 1,3,5-Me3C6H3 (1), p-MeC6H4CHMe2 (2), C6Me6 (3), p-MeC6H4Me (4), MeC6H5 (5)) dimers react with diphenylvinylphosphine (DPVP) to produce [(η6-1,3,5-Me3C6H3)Ru(DPVP)Cl2] (1a), [(η6-p-MeC6H4CHMe2)Ru(DPVP) Cl2] (2a), [(η6-C6Me6)Ru(DPVP)Cl2] (3a), [(η6-p-MeC6H4Me)Ru(DPVP)Cl2] (4a), and [(η6-MeC6H5)Ru(DPVP)Cl2] (5a). In acetonitrile, compounds 1−5 undergo base-promoted hydroalkylation reactions with potassium tert-butoxide and diphenylvinylphosphine to produce [{η6-3,5-Me2C6H3-1-CH2CH2CH2P(C6H5)2}RuCl2] (1b), [{η6-p-Me2CHC6H4CH2CH2CH2P(C6H5)2}RuCl2] (2b), [{η6-C6Me5CH2CH2CH2P(C6H5)2}RuCl2] (3b), [{η6-p-MeC6H4CH2CH2CH2P(C6H5)2}RuCl2] (4b), and [{η6-C6H5CH2CH2CH2P(C6H5)2}RuCl2] (5b). The reaction with the p-MeC6H4CHMe2 complex proceeds regioselectively at the methyl group to produce the most stable product. All the complexes have been characterized spectroscopically and the crystal structures of several of them have been obtained.