Mechanistic studies on ruthenium-catalyzed hydrogen transfer reactions

Reactions of Ru(Cp∗) complexes with P(o-tolyl)3

“…Crystals of the pure monosubstituted phosphite complex were obtained by dissolving 50 mg of the yellow solid in acetone, layering with diethyl ether and cooling to À40°C (%). 1 [RuCp * (tris(2,4-di-tert-butylphenyl)phosphite) (CH 3 -CN) 2 ]PF 6 (14). A solution of tris(2,4-di-tert-butylphenyl)phosphite (149.5 mg, 0.231 mmol) in 3 mL acetone was added to a solution of [RuCp * (CH 3 CN) 3 ]PF 6 (106.0 mg, 0.210 mmol) in 3 mL acetone.…”

“…Reaction of [Ru(Cp * )(CH 3 CN) 3 ](PF 6 ) with 1.1 equiv. of the phosphite 12 resulted in the mono-phosphite complex, Ru(Cp * )-(12)(CH 3 CN) 2 ](PF 6 ) (14) with no trace of arene complexed species observable in the 1 H NMR spectrum. Product 13, Ru(Cp * ) (11)(CH 3 CN) 2 ](PF 6 ), could be isolated by layer- ing an acetone solution of the crude product with diethyl ether and cooling to À40°C.…”

“…The now readily available Ru(II) salts, [Ru(Cp or Cp * )(CH 3 CN) 3 ](PF 6 ) [4e], have been widely employed as starting materials in the synthesis, study and catalytic reactions of an increasing number of half sandwich complexes. Equally popular are the Ru-g 6 -arene complexes [15][16][17] and/or complexes that contain tertiary phosphine ligands [1,2,5,6,8,[14][15][16][17].…”

“…A variety of complexes of ruthenium continue to attract interest both for their organometallic and catalytic chemistry [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. The now readily available Ru(II) salts, [Ru(Cp or Cp * )(CH 3 CN) 3 ](PF 6 ) [4e], have been widely employed as starting materials in the synthesis, study and catalytic reactions of an increasing number of half sandwich complexes.…”

The biphasic transfer hydrogenation of aldehydes and ketones with isopropanol catalyzed by water-soluble rhodium complexes

“…Among the methods used, transfer hydrogenation [1] is an elegant strategy that can be accomplished with homogeneous [2][3][4][5][6][7][8][9][10], heterogeneous [11][12][13][14][15][16][17][18], perfluorenated [19], and water-soluble catalysts [20-23], using different hydrogen sources such as isopropanol and formic acid derivatives.…”