title: Synthesis of Silver(I) and Gold(I) Complexes Containing Enantiopure Pybox Ligands. First Assays on the Silver(I)-Catalyzed Asymmetric Addition of Alkynes to Imines.
abstract: Dinuclear complexes [Ag2(CF3SO3){(S,S)-(i)Pr-pybox}2][CF3SO3] (1), [Ag2(R-pybox)2][X]2 [R-pybox = 2,6-bis[4-(S)-isopropyloxazolin-2-yl]pyridine (S,S)-(i)Pr-pybox and X = PF6 (2) and BF4 (3); R-pybox = 2,6-bis[(3aS,8aR)-8,8a-dihydro-3aH-indeno[1,2-d]oxazol-2-yl]pyridine (3aS,3a'S,8aR,8a'R)-indane-pybox and X = CF3SO3 (4)], [Ag2{(S,S)-(i)Pr-pybox}{(3aS,3a'S,8aR,8a'R)-indane-pybox}][CF3SO3]2 (5), and [Ag2(R-pybox)3][X]2 [R-pybox = (3aS,3a'S,8aR,8a'R)-indane-pybox and X = CF3SO3 (10), SF6 (11), and PF6 (12)] as well as mononuclear complexes [Ag(R-pybox)2][X] [R-pybox = (S,S)-(i)Pr-pybox and X = SbF6 (6), PF6 (7), and BF4 (8); R-pybox = (3aS,3a'S,8aR,8a'R)-indane-pybox) and X = BF4 (9)] have been prepared by the reaction of the corresponding silver salts and pybox ligands using the appropriate molar ratio conditions. The first gold(I)/pybox complex [Au6Cl4{(S,S)-(i)Pr-pybox}4][AuCl2]2 (13) has been synthesized by the reaction of [AuCl{S(CH3)2}] and (S,S)-(i)Pr-pybox (1:1 molar ratio) in acetonitrile. The structures of the dinuclear (1, 4, 5, 10, and 11) and mononuclear (6 and 9) silver complexes and the hexanuclear gold complex 13 have been determined by single-crystal X-ray diffraction analysis. These studies have been complemented with a solution-state study by NMR spectroscopy, which included structure elucidation, variable-temperature measurements, and diffusion studies using diffusion-ordered spectroscopy (DOSY; for complexes 1, 4, 10, and 12). Complexes 1, 2, 4, and 10 have been assayed as catalysts in the asymmetric addition of phenylacetylene to N-benzylideneaniline.
authors: Departamento de Química Orgánica e Inorgánica, IUQOEM (Unidad Asociada al CSIC), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Oviedo , E-33006 Oviedo, Principado de Asturias, Spain.
authors: Gustavo M
authors: GM
authors: Borrajo-Calleja
authors: Departamento de Química Orgánica e Inorgánica, IUQOEM (Unidad Asociada al CSIC), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Oviedo , E-33006 Oviedo, Principado de Asturias, Spain.
authors: Eire
authors: E
authors: de Julián
authors: Departamento de Química Orgánica e Inorgánica, IUQOEM (Unidad Asociada al CSIC), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Oviedo , E-33006 Oviedo, Principado de Asturias, Spain.
authors: Esther
authors: E
authors: Bayón
authors: Departamento de Química Orgánica e Inorgánica, IUQOEM (Unidad Asociada al CSIC), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Oviedo , E-33006 Oviedo, Principado de Asturias, Spain.
authors: Josefina
authors: J
authors: Díez
authors: Departamento de Química Orgánica e Inorgánica, IUQOEM (Unidad Asociada al CSIC), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Oviedo , E-33006 Oviedo, Principado de Asturias, Spain.
authors: Elena
authors: E
authors: Lastra
authors: Unidad de Resonancia Magnética Nuclear, Servicios Científico-Técnicos de la Universidad de Oviedo , E-33006 Oviedo, Principado de Asturias, Spain.
authors: Isabel
authors: I
authors: Merino
authors: Departamento de Química Orgánica e Inorgánica, IUQOEM (Unidad Asociada al CSIC), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Oviedo , E-33006 Oviedo, Principado de Asturias, Spain.
authors: M Pilar
authors: MP
authors: Gamasa