Hydrophilic (η6-Arene)–Ruthenium(II) Complexes with P–OH Ligands as Catalysts for the Isomerization of Allylbenzenes and C–H Bond Arylation Reactions in Water

Half-sandwich ruthenium(II) complexes containing η6-coordinated 3-phenylpropanol and phosphinous-acid-type ligands, namely, [RuCl2(η6-C6H5CH2CH2CH2OH){P(OH)R2}] (R = Me (2a), Ph (2b), 4-C6H4CF3 (2c), 4-C6H4OMe (2d), OMe (2e), OEt (2f), and OPh (2g), have been synthesized in 44–88% yield by reacting...

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Detalles Bibliográficos
Autores: González-Fernández, Rebeca, Crochet, Pascale, Cadierno, Victorio
Tipo de recurso: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2019
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/209821
Acceso en línea:http://hdl.handle.net/10261/209821
Access Level:acceso abierto
Palabra clave:Isomerization
Reactions in water
Descripción
Sumario:Half-sandwich ruthenium(II) complexes containing η6-coordinated 3-phenylpropanol and phosphinous-acid-type ligands, namely, [RuCl2(η6-C6H5CH2CH2CH2OH){P(OH)R2}] (R = Me (2a), Ph (2b), 4-C6H4CF3 (2c), 4-C6H4OMe (2d), OMe (2e), OEt (2f), and OPh (2g), have been synthesized in 44–88% yield by reacting [RuCl2{η6:κ1(O)-C6H5CH2CH2CH2OH}] (1) with the appropriate pentavalent phosphorus oxide R2P(═O)H. The structure of [RuCl2(η6-C6H5CH2CH2CH2OH){P(OH)Me2}] (2a) was unequivocally confirmed by X-ray diffraction methods. Compounds 2a–g proved to be catalytically active in the isomerization of allylbenzenes into the corresponding (1-propenyl)benzene derivatives employing water as the sole reaction solvent, with [RuCl2(η6-C6H5CH2CH2CH2OH){P(OH)(OPh)2}] (2g) showing the best performance and a broad substrate scope (73–93% isolated yields with E/Z ratios around 90:10 employing 1 mol % of 2g and 3 mol % of K2CO3, and performing the catalytic reactions at 80 °C for 4–24 h). The results herein presented show for the first time the utility of phosphinous acids as auxiliary ligands for metal-catalyzed olefin isomerization processes, reactions in which a cooperative role for the P—OH unit is proposed. On the other hand, the utility of complexes 2a–g as catalysts for ortho-arylation reactions of 2-phenylpyridine in water is also briefly discussed.