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The alkoxide [Ru(O<jats:italic>i<\/jats:italic>Pr)(CNN)(dppb)] (<jats:bold>4<\/jats:bold>) is formed by treatment of the hydride [Ru(H)(CNN)(dppb)] (<jats:bold>2<\/jats:bold>) with acetone in C<jats:sub>6<\/jats:sub>D<jats:sub>6<\/jats:sub>. Complex <jats:bold>5<\/jats:bold> in 2\u2010propanol\/C<jats:sub>6<\/jats:sub>D<jats:sub>6<\/jats:sub> equilibrates quickly with hydride <jats:bold>2<\/jats:bold> and acetone with an exchange rate of (5.4\u00b10.2)\u2005s<jats:sup>\u22121<\/jats:sup> at 25\u2009\u00b0C, higher than that found between <jats:bold>4<\/jats:bold> and <jats:bold>2<\/jats:bold> ((2.9\u00b10.4)\u2005s<jats:sup>\u22121<\/jats:sup>). This fast process, involving a \u03b2\u2010hydrogen elimination versus ketone insertion into the Ru\uf8ffH bond, occurs within a hydrogen\u2010bonding network favored by the Ru\uf8ffNH<jats:sub>2<\/jats:sub> motif. The cationic alcohol complex [Ru(CNN)(dppb)(<jats:italic>i<\/jats:italic>PrOH)](BAr<jats:sup>f<\/jats:sup><jats:sub>4<\/jats:sub>) (<jats:bold>6<\/jats:bold>; Ar<jats:sup>f<\/jats:sup>=3,5\u2010C<jats:sub>6<\/jats:sub>H<jats:sub>3<\/jats:sub>(CF<jats:sub>3<\/jats:sub>)<jats:sub>2<\/jats:sub>), obtained from <jats:bold>1<\/jats:bold>, Na[BAr<jats:sup>f<\/jats:sup><jats:sub>4<\/jats:sub>], and 2\u2010propanol, reacts with NaO<jats:italic>i<\/jats:italic>Pr to afford <jats:bold>5<\/jats:bold>. Complex <jats:bold>5<\/jats:bold> reacts with either 4,4\u2032\u2010difluorobenzophenone through hydride <jats:bold>2<\/jats:bold> or with 4,4\u2032\u2010difluorobenzhydrol through protonation, affording the alkoxide [Ru{OCH(4\u2010C<jats:sub>6<\/jats:sub>H<jats:sub>4<\/jats:sub>F)<jats:sub>2<\/jats:sub>}(CNN)(dppb)] (<jats:bold>7<\/jats:bold>) in 90 and 85\u2009% yield of the isolated product. The chiral CNN\u2013ruthenium compound [RuCl(CNN){(<jats:italic>S<\/jats:italic>,<jats:italic>S<\/jats:italic>)\u2010Skewphos}] (<jats:bold>8<\/jats:bold>), obtained by the reaction of [RuCl<jats:sub>2<\/jats:sub>(PPh<jats:sub>3<\/jats:sub>)<jats:sub>3<\/jats:sub>] with (<jats:italic>S<\/jats:italic>,<jats:italic>S<\/jats:italic>)\u2010Skewphos and orthometalation of HCNN in the presence of NEt<jats:sub>3<\/jats:sub>, is a highly active catalyst for the enantioselective transfer hydrogenation of methylaryl ketones (turnover frequencies (TOFs) of up to 1.4\u00d710<jats:sup>6<\/jats:sup>\u2005h<jats:sup>\u22121<\/jats:sup> at reflux were obtained) with up to 89\u2009%\u2005<jats:italic>ee<\/jats:italic>. Also the ketone CF<jats:sub>3<\/jats:sub>CO(4\u2010C<jats:sub>6<\/jats:sub>H<jats:sub>4<\/jats:sub>F), containing the strong electron\u2010withdrawing CF<jats:sub>3<\/jats:sub> group, is reduced to the <jats:italic>R<\/jats:italic>\u2005alcohol with 64\u2009%\u2005<jats:italic>ee<\/jats:italic> and a TOF of 1.5\u00d710<jats:sup>4<\/jats:sup>\u2005h<jats:sup>\u22121<\/jats:sup>. The chiral alkoxide [Ru(O<jats:italic>i<\/jats:italic>Pr)(CNN){(<jats:italic>S<\/jats:italic>,<jats:italic>S<\/jats:italic>)\u2010Skewphos}]<jats:bold>\u22c5<\/jats:bold><jats:italic>n<\/jats:italic>\u2009<jats:italic>i<\/jats:italic>PrOH (<jats:bold>9<\/jats:bold>), obtained from <jats:bold>8<\/jats:bold> and NaO<jats:italic>i<\/jats:italic>Pr in the presence of 2\u2010propanol, reacts with CF<jats:sub>3<\/jats:sub>CO(4\u2010C<jats:sub>6<\/jats:sub>H<jats:sub>4<\/jats:sub>F) to afford a mixture of the diastereomer alkoxides [Ru{OCH(CF<jats:sub>3<\/jats:sub>)(4\u2010C<jats:sub>6<\/jats:sub>H<jats:sub>4<\/jats:sub>F)}(CNN){(<jats:italic>S<\/jats:italic>,<jats:italic>S<\/jats:italic>)\u2010Skewphos}] (<jats:bold>10<\/jats:bold>\/<jats:bold>11<\/jats:bold>; 74\u2009% yield) with 67\u2009%\u2005<jats:italic>de<\/jats:italic>. This value is very close to the enantiomeric excess of the alcohol (<jats:italic>R<\/jats:italic>)\u2010CF<jats:sub>3<\/jats:sub>CH(OH)(4\u2010C<jats:sub>6<\/jats:sub>H<jats:sub>4<\/jats:sub>F) formed in catalysis, thus suggesting that diastereoisomeric alkoxides with the Ru\uf8ffNH<jats:sub>2<\/jats:sub> linkage are key species in the catalytic asymmetric transfer hydrogenation reaction.<\/jats:p>","DOI":"10.1002\/chem.200701870","type":"journal-article","created":{"date-parts":[[2008,4,2]],"date-time":"2008-04-02T10:58:18Z","timestamp":1207133898000},"page":"5588-5595","source":"Crossref","is-referenced-by-count":66,"title":["Role of the NH<sub>2<\/sub> Functionality and Solvent in Terdentate CNN Alkoxide Ruthenium Complexes for the Fast Transfer Hydrogenation of Ketones in 2\u2010Propanol"],"prefix":"10.1002","volume":"14","author":[{"given":"Walter","family":"Baratta","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maurizio","family":"Ballico","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gennaro","family":"Esposito","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pierluigi","family":"Rigo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2008,6,11]]},"reference":[{"key":"e_1_2_6_1_2","unstructured":"\u00a0"},{"key":"e_1_2_6_2_2","doi-asserted-by":"publisher","DOI":"10.1039\/b515269k"},{"key":"e_1_2_6_3_2","doi-asserted-by":"publisher","DOI":"10.1039\/B513396C"},{"key":"e_1_2_6_4_2","doi-asserted-by":"publisher","DOI":"10.1039\/B513564H"},{"key":"e_1_2_6_5_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.ccr.2004.04.007"},{"key":"e_1_2_6_6_2","doi-asserted-by":"publisher","DOI":"10.1002\/adsc.200390030"},{"key":"e_1_2_6_7_2","unstructured":"\u00a0"},{"key":"e_1_2_6_8_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja991638h"},{"key":"e_1_2_6_9_2","doi-asserted-by":"publisher","DOI":"10.1002\/ange.19971090333"},{"key":"e_1_2_6_9_3","doi-asserted-by":"publisher","DOI":"10.1002\/anie.199702851"},{"key":"e_1_2_6_10_2","unstructured":"\u00a0"},{"key":"e_1_2_6_11_2","doi-asserted-by":"publisher","DOI":"10.1002\/chem.200700373"},{"key":"e_1_2_6_12_2","doi-asserted-by":"publisher","DOI":"10.1002\/1521-3765(20011203)7:23<5052::AID-CHEM5052>3.0.CO;2-Z"},{"key":"e_1_2_6_13_2","doi-asserted-by":"publisher","DOI":"10.1039\/a809236b"},{"key":"e_1_2_6_14_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja062359e"},{"key":"e_1_2_6_15_2","unstructured":"\u00a0"},{"key":"e_1_2_6_16_2","volume-title":"Alkoxo and Aryloxo Derivatives of Metals","author":"Bradley D. 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