96193-47-4Relevant academic research and scientific papers
Stereochemistry of some ligand substitution and insertion reactions in pseudotetrahedral ruthenium(II) complexes
Morandini, Franco,Consiglio, Giambattista,Lucchini, Vittorio
, p. 1202 - 1208 (1985)
Pseudotetrahedral (SRu,RC)-1 and (RRu,Rc)-(η-C5H5)Ru(prophos)Cl, 1′ (where prophos is (R)-1,2-propanediylbis(diphenylphosphine)). react with CH3MgBr or C2H5MgBr to give the alkylation products (SRu,RC)-2 and (RRu,RC)-(η-C5,H5)Ru(prophos)R, 2′ (R = CH3, a; R = C2H5, b), with stereospecific retention of configuration at the ruthenium atom. With C2H5MgBr also a competitive formation of the corresponding hydrides (SRu,RC)-3 and (RRu,RC)-(η-C5H5)Ru(prophos)H, 3′, takes place. Hydride formation is the only reaction observed when 1 or 1′ is reacted with sec-C4H9MgBr and, according to NOE experiments, takes also place with retention of configuration. Under the conditions of their formation (or even under more severe conditions) 2b and 2b′ do not thermally decompose to 3 or 3′. Hydride formation is therefore not a consequence of alkylation followed by β-hydrogen elimination but must arise from a different reaction pathway whose possible nature is discussed. Hydrides 3 and 3′ react with CH2N2 in the presence of catalytic amounts of Pd(CH3COO)2, to give the methyl derivatives 2a and 2a′ with retention of configuration. Stereospecific retention of configuration is also observed in the formation of 3 and 3′ when 1 and 1′ are treated with CH3ONa. By contrast, the reaction of 1 and 1′ and that of (SRu,RC)-4 and (RRu,RC)-[(η-C5H 5)Ru(prophos)(CH3CN)]PF6, 4′, with HCOONa is stereoselective; in the first case 3 and 3′ were obtained in a 20:80 and in the second one in a 40:60 molar ratio. 1 and 1′ form from the hydrides 3 and 3′ when treated with CDCl3 or CCl4 in a stereoselective reaction. Predominant inversion of configuration is observed in the reaction of 4 and 4′ with (C6H5)4AsCl to give 1 and 1′.
