Shape Selectivity in the Gold-Catalyzed Hydration of Alkynes Using a Cavity-Shaped Phosphine
Miquel Navarro1, Markus Holzapfel1,2, Jesús Campos1
1Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Sevilla and Consejo Superior de Investigaciones Científicas (CSIC)., Avenida Américo Vespucio 49, 41092, Sevilla, Spain.
Abstract:
A cavity-shaped gold(I) complex derived from a bulky tri-(ortho-biaryl)-phosphine ligand shows preferred selectivity towards terminal functionalities in the gold(I)-catalysed hydration of alkynes under mild heating due to a well-defined pocket as catalytic active site. The confinement-induced size-exclusion selectivity investigated for eight alkynes contrasts with other gold(I) complexes bearing bulky phosphine ligands that show reduced selectivity or even similar behaviour towards both internal and terminal alkynes. We also interrogate the potential of gold(III) derivatives for the same catalytic process.
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