Highly selective hydrogenation of quinolines promoted by recyclable polymer supported palladium nanoparticles under mild conditions in aqueous medium

Preparation of highly active and hydrothermally stable nickel catalysts

“…The hydrogenation reactions are widely applied in industry [5]. The hydrogenation reactions with the solvent of water have been developed and used in industries [6][7][8]. For instance, sorbitol is an important chemical widely used in food, cosmetic, paper and other fine chemical industries.…”

A polymer supported palladium(II) β-ketoesterate complex as active and recyclable pre-catalyst for selective reduction of quinolines in water with sodium borohydride

“…Following our studies, herein we report on the ability of Pdpol to efficiently catalyze the selective reduction of quinolines into tetrahydroquinolines in neat water using NaBH 4 as hydrogen source, thus using "safer" conditions compared to the ones previously proposed by us [57].…”

“…In fact, Pd-pol was active and recyclable in the Suzuki cross coupling of arylhalides with arylboronic acids [54], the aerobic selective oxidation of benzyl alcohols [55] and the reduction of nitroarenes [56], all of them carried out in water. Moreover, Pd-pol was already tested in aqueous medium as catalyst for the hydrogenation of quinolines into 1,2,3,4-tetrahydroquinolines at 80 • C under 10 bar H 2 , resulting uncommonly recyclable at least for nine consecutive runs with high yields [57]. To the best of our knowledge, Pd-pol is still the second example reported to date of active palladium catalyst recyclable in aqueous solvent for the selective hydrogenation of quinolines and heteroaromatic nitrogen compounds under mild conditions using hydrogen gas, being the first reported example Pd nanoparticles on black wattle tannin [28,29].…”

Esterification, transesterification and hydrogenation reactions of polyunsaturated compounds catalyzed by a recyclable polymer supported palladium catalyst

“…A C C E P T E D Pd-pol pre-catalyst was successfully employed in several palladium promoted reactions [26,27,28,29,30,31,32,33,34,35]. In all cases, the pristine Pd(II) supported complex was reduced in situ under reaction conditions to Pd(0), forming palladium nanoparticles (NPs) (the real active species) immobilized onto the insoluble support (Pd-pol, Scheme 1) and stabilized by the macroporous and reticulated polymer matrix [36].…”