Selective hydrogenation of the C O bond of ketones using Ni(0) complexes with a chelating bisphosphine

• Published in: Journal of molecular catalysis. A, Chemical Vol. 309; no. 1; pp. 1 - 11
• Main Authors: Flores-Gaspar, Areli, Pinedo-González, Paulina, Crestani, Marco G., Muñoz-Hernández, Miguel, Morales-Morales, David, Warsop, Brian A., Jones, William D., García, Juventino J.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 18.08.2009; Elsevier
• Subjects: Catalysis; Chemistry; Diphosphine; Exact sciences and technology; General and physical chemistry; Homogeneous catalysis; Hydrogenation; Ketone; Nickel; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Diphosphine; Nickel; Ketone; Hydrogenation; Homogeneous catalysis; Transition element complexes; Chelating agent; Organic ligand; Transition metal; Nickel complex; Diphosphane; Benzophenone
• ISSN: 1381-1169; 1873-314X
• DOI: 10.1016/j.molcata.2009.05.026

The nickel complexes [(dippe)Ni(η 2- O, C-benzophenone)] ( 2), [(dippe)Ni(η 2- O, C-4-methylbenzophenone)] ( 3), [(dippe)Ni(η 2- O, C-acetophenone)] ( 4), [(dippe)Ni(η 2- O, C-acetone)] ( 5), [(dippe)Ni(η 2- O, C-fluorenone)] ( 6), [(dippe)Ni(η 2- O, C-di(2-pyridyl) ketone)] ( 7a) [(dippe)Ni(κ 2- N, N-di(2-pyridyl) ketone)] ( 7b), [(dippe)Ni(κ 2- O, O-2,2′-pyridil)] ( 8), [(dippe)Ni(κ 2- O, O-benzil)] ( 9a), and [((dippe)Ni) 2(η 2- O, C-benzil)] ( 9b) were prepared by the reaction of [(dippe)Ni(μ-H)] 2 ( 1) with the corresponding ketone or 1,2-diketone at room temperature. The structures of compounds 2, 6, 9a and 9b were confirmed by X-ray crystallography. The selective hydrogenation of the two types of substrates was undertaken using H 2, giving high conversions to the corresponding reduction products, either alcohols or alkanes. Tunable reaction conditions to promote the partial or total hydrogenation (hydrogenolysis) of the substrates are described. The reduction of ketones and diketones to yield an alcohol or alkane can be selectively achieved with nickel complexes and properly selecting the reaction conditions.