Studien zur C-H-Aktivierung IV. Inter- and Intra-molekulare C-H-Aktivierung mit Komplexfragmenten des Typs (M=Ru, Os)

Article abstract of DOI:10.1016/0022-328X(88)89040-5

The dihydro ruthenium and osmium complexes C6H6RuH2(PPrⁱ₃), C6Me6RuH2 (R=Me, Prⁱ) and C6H6OsH2(PPrⁱ₃) can be obtained from the corresponding dihalogeno derivatives C6R6MX2(L) (X=Cl,I) and NaBH4 or Na.Photolysis, in presence of benzene and toluene, of C6H6RuH2(PPrⁱ₃) or C6Me6RuH2(PMe3) gives the hydrido(phenyl) and hydrido(tolyl) complexes, C6H6RuH(C6H4R)(PPrⁱ₃) or C6Me6RuH(C6H4R)(PMe3) (R=H, Me) in 35-63percent yield.C6H6RuH(C6H4Me)(PPrⁱ₃) or C6Me6RuH(C6H4Me)(PMe3) can also be prepared from C6H6RuBr(C6H4Me)(PPrⁱ₃) or C6Me6RuBr(C6H4Me)(PMe3) and NaBH4 in ethanol.Photolysis of C6H6RuH2(PPrⁱ₃ ) in cyclohexane, hexane of mesitylene leads to the formation of the four-membered metallaheterocycle C6H6(H)RuCH2CH(CH3)PPⁱ2<*> which can be isolated as a pair of diastereomers.It reacts smoothly with C6H6, C6D6 and C6H5Me in the dark to give the corresponding aryl(hydrido)ruthenium compounds C6H6RuH(C6H4R)(PPrⁱ₃) (R=H, Me) and C6H6RuD(C6D5)(PPrⁱ₃) in almost quantitative yield.In contrast to C6H6RuH2(PPrⁱ₃), the corresponding osmium complex C6H6OsH2(PPrⁱ₃) is photochemically inert.C6H6OsH(C6H5)(PPrⁱ₃), C6H6OsH(C6H5)(PMe3) and C6H6OsD(C6D5)(PMe3) have been obtained from the reaction of C6H6OsI2(PR3) (R=Me, Prⁱ) with NaC10H8 in THF/C6H6 or C6D6, by the classical Chatt route.