Reactions of [RuClH(CO)(PPh3)(3)] with 2-methyl-2-propen-1-ol. Reversible insertion/beta-elimination, and reductive elimination on a 3-hydroxy-2-methylpropyl-C-1,O-ruthenium(II) complex

A hydridoruthenium complex [RuClH(CO)(PPh3)(3)] (1) reacts with 2-methyl-2- propen-1-ol at room temperature to give an insertion product, [Ru{CH2CH(CH3 )CH2OH}Cl(CO)(PPh3)(2)] (2), which undergoes beta-elimination of 2-methyl-2 -propen-1-ol reversibly in solution. The complex 1 reacts with 2-methyl-2-p ropen-1-ol under benzene refluxing conditions to produce 2-methylpropan-1-o l, 2-methylpropanal and 2-methyl-2-propenal catalytically in the presence o f water. The production of 2-methylpropanal results in formation of two iso mers of 2-methylpropanoato complex [RuCl{eta(2)-(CH3)(2)CHCO2}(CO)(PPh3)(2) ] (3). Heating 1 at 80 degrees C in neat 2-methyl-2-propen-1-ol affords a n ovel ruthenium(O) complex [Ru{eta(4)-CH2=C(CH3)CH=O}(CO)(PPh3)(2)] (7) and a quaternary phosphonium salt [Ph3PCH2CH(CH3)CH2OH]Cl (8) via reductive eli mination of 3-chloro-2methylpropan-1-ol from 2. The molecular structures of 7 and 8 are determined by X-ray crystallography. (C) 1999 Elsevier Science S.A. All rights reserved.