A series of ruthenium(II) complexes containing the bulky, functionalized trialkylphosphines tBu_2PCH_2XC_6H_5 as ligands

摘要

The monomeric ruthenium(II) complexes [(#eta#~6-C_6H_5XCH_2PtBu_2-#kappa#-P)RuCl_2] 3, 4 were prepared either on a reductive route from RuCl_3(centre dot)3H_2O and tBu_2PCH_2XPh (X = CH_2 1, OCH_2 2) or by ligand replacement reactions from [(p-cym)RuCl_2]_2 and the phosphine via the p-cymene compounds [(p-cym)(C_6H_5XCH_2PtBu_2-#kappa#-P)RuCl_2] 6, 7 as intermediates. Abstraction of one chloro ligand from 3 with AgPF_6 led to the formation of the dinuclear complex [{(#eta#~6-C_6H_5CH_2PtBu_2-#kappa#-P)RuCl_2}(PF_6)_2 8, which reacts with acetone, CH_3CN and PMe_3 by bridge cleavage to afford the mononuclear compounds [(#eta#~6-C_6H_5CH_2PtBu_2-#kappa#-P)RuCl(L)]PF_6 9, 10, 12. Both 10 and 11 (the latter containing 2 as chelating ligand) were also obtained form 3, 4 and AgPF_6 in the presence of acetonitrile. Hydridoruthenium(II) complexes [(#eta#~6-C_6H_5XCH_2PtBu_2-#kappa#-P)RuHCl] 13, 14, [RuHCl(H_2)(L)_2] 15 (L = 1), 16 (L = 2) and [RuHCl(CO)(2)_2] 17 could be prepared from RuCl_3(centre dot)3H_2O and 1 or 2 in the presence of Net_3 under reductive conditions. Insertion, substitution and addition reactions of compound 17 led to the formation of [Ru(CH=CH_2)Cl(CO)(2)_2] 18, [RuHF(CO)(2)_2] 19, and [RuHCl(CO)_2(2)_2] 20, respectively. The cationic allenylidene complexes [(#eta#~6-C_6H_5XCH_2PtBu_2-#kappa#-P)RuCl(=C=C=CPh_2)]A 22a,b (X = CH_2; A = BF_4, PF_6) and 23 (X = OCH_2; A = PF_6) were prepared from 3,4 or 13, HC(ident to)CC(OH)Ph_2 and either one equiv. of AgPF_6 or an equivalent amount of HBF_4 in diethyl ether. Treatment of 15 and 16 with acetylene afforded the five-coordinate vinylideneruthenium(II) compounds [RuHCl(=C=CH_2)(L)_2]24, 25 which in the presence of HBF_4 are highly efficient catalysts for the Ring Opening Metathesis Polymerization (ROMP) of cyclooctene. The molecular structures of 10 and 17 were determined rystallographically.