title: Well-Defined Noble Metal Single Sites in Zeolites as an Alternative to Catalysis by Insoluble Metal Salts.
abstract: Insoluble precious metal chlorides in polymeric form (i.e., PtCl2, PdCl2, AuCl, RhCl3) are commonly used as catalysts for a plethora of organic reactions in solution. Here we show that only the minor soluble fraction of these precious metal chlorides (typically 5-30%) is catalytically active for the hydroamination, hydroalkoxylation, hydrosilylation, and cycloisomerization of alkynes and alkenes, and that the resting insoluble metal is catalytically useless. To circumvent this waste of precious metal and follow a rational design, we generate here well-dispersed Pt(II) and Pd(II) single sites on zeolite Y, with an exquisite control of the Lewis acidity, to catalyze different hydroaddition reactions to alkynes and alkenes with up to 10(4) catalytic cycles (at least 2 orders of magnitude superior to precious metal chlorides) and with high isolated yields (82-99%, >15 examples).
authors: Instituto de Tecnología Química, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas , Avda. de los Naranjos s/n, 46022 Valencia, Spain.
authors: Paula
authors: P
authors: Rubio-Marqués
authors: Instituto de Tecnología Química, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas , Avda. de los Naranjos s/n, 46022 Valencia, Spain.
authors: Miguel A
authors: MA
authors: Rivero-Crespo
authors: Instituto de Tecnología Química, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas , Avda. de los Naranjos s/n, 46022 Valencia, Spain.
authors: Antonio
authors: A
authors: Leyva-Pérez
authors: Instituto de Tecnología Química, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas , Avda. de los Naranjos s/n, 46022 Valencia, Spain.|King Fahd University of Petroleum and Minerals, Dhahran, 31261 Saudi Arabia.
authors: Avelino
authors: A
authors: Corma