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A highly selective double reductive aminations of aldehydes with anilines to give tertiary amines, in the presence of [RuCl 2 ( p -cymene)] 2 catalyst and PhSiH 3 , was performed under neat conditions. Piperidine derivatives were successfully synthesized by a double reductive amination followed by cyclisation from glutaric dialdehyde with anilines. [ABSTRACT FROM AUTHOR]

An efficient ruthenium catalyst system for the direct ortho C H borylation of aromatic imines is described. The reaction of tert -butyl-1-arylmethanimines with pinacolborane in the presence of Ru(cod)(cot), followed by hydrolysis, to afford the ortho-formyl-substituted arylboronates. The borylation was achieved with complete mono-selectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] An atom-economy, two-step synthesis of 2 H -1,2,3-triazole-4-carboxylic acids from 3-arylisoxazol-5(4 H)-ones and arenediazonium tetrafluoroborates is described. The formation of the 1,2,3-triazole ring is achieved by the [Ru(p -cymene)Cl 2 ] 2 -catalyzed rearrangement of 4-hydrazonoisoxazol-5-ones which are resulted from the diazo coupling. The advantages of the method include the available starting compounds and the ability to purify target acids without the use of chromatography. [ABSTRACT FROM AUTHOR]

An environmentally benign alkylation of barbituric acids via “borrowing hydrogen” process with ruthenium catalysis has been established. The corresponding 5-(alkyl)barubituric acids were obtained in good to excellent yields with low catalyst loading. Various substrates including aliphatic alcohols were tolerated in the present catalytic system. A novel method for construction of barbituric acid-fused benzopyrane derivatives was also demonstrated. [ABSTRACT FROM AUTHOR]

The direct reductive N -benzylation of imines by reaction with benzyl bromide derivatives, in the presence of [RuCl 2 ( p -cymene)] 2 catalyst and PhSiH 3 , is performed under mild conditions without additional base. This reaction proceeds by a tandem imine hydrosilylation/nucleophilic substitution with benzyl bromide derivatives to result the tertiary amines. [ABSTRACT FROM AUTHOR]

Abstract: The electrophilic α-alkylation of ketones with alcohols was accomplished by a [Ru(DMSO)4]Cl2 catalyzed process, water being the only wasted material. The reaction can be successfully governed to produce either the expected ketones or their related alcohols only by changing the reaction conditions. When 2-aminobenzyl alcohol was used, a cyclization process took place to yield 2,3-disubstituted quinolines. [Copyright &y& Elsevier]

[Display omitted] • Ruthenium-catalyzed stereospecific benzylic alkylation of optically active benzyl esters. • Malonates are used as a carbon nucleophile. • The Ru-catalyzed stereospecific reaction would proceed via a double inversion mechanism. The transition metal-catalyzed stereospecific benzylic alkylation of optically active benzyl esters with active methylene compounds remains extremely rare. Herein, we describe the study for the ruthenium-catalyzed benzylic alkylation of chiral benzyl esters with malonates as a carbon nucleophile. A combination of [Cp*RuCl 2 ] 2 and picolinic acid found to be effective for the title reaction, providing the chiral benzylic alkylation products with retention of stereochemistry of the starting material. We proposed that the ruthenium catalysis would proceed via a double inversion mechanism. [ABSTRACT FROM AUTHOR]

• Compatible redox with simple catalytic system. • One-pot deracemization transformation. • Wide substrate scope and good enantioselectivity. The deracemization of benzylic alcohols has been achieved using a redox-driven one-pot two-step process. The racemic alcohols were oxidized by bis(methoxypropyl) ether and oxygen to give the ketone intermediates, followed by an asymmetric transfer hydrogenation with a chiral ruthenium catalyst. This compatible oxidation/reduction process gave the enantiomerically enriched alcohols with up to 95% ee values. [ABSTRACT FROM AUTHOR]