Gold nanoparticles supported on functionalized oxides as catalysts for organic transformations in batch and flow systems

Our research group has previously reported the preparation of gold nanoparticles (AuNPs) anchored on different functionalized silica supports, i.e. commercial polyethyleneimine-functionalized silica beads [1] and silica nanoparticles functionalized with alkynyl carbamate moieties [2]. Moreover, we have recently focused on the straightforward synthesis of AuNPs anchored on commercial, micrometric oxide supports (SiO2, Al2O3, TiO2) previously modified with the di-functional organosilane [3-(2-propynylcarbamate)propyl]triethoxysilane (PPTEOS) by a grafting procedure. After being thoroughly characterized by several complementary techniques (XPS, TEM, SSNMR, AAS etc.), the catalytic activity of these systems (Au/OS@Yne) has been evaluated in the oxidation of alcohols both in batch and continuous-flow systems [3]. Successively, we have carried on with the deposition of AuNPs on organic modified Fe3O4 obtaining an easy recoverable magnetic catalyst. After an extended characterization, the catalytic activity of Au/Fe3O4@Yne has been evaluated in the alkynes hydroamination reaction and the results have been compared with the ones obtained with Au/SiO2@Yne. References [1] S. Fazzini , D. Nanni , B. Ballarin , M. C. Cassani , M. Giorgetti , C. Maccato, A. Trapananti, G. Aquilanti and S. I. Ahmed, J. Phys. Chem. C. 116 (2012) 25434−25443; M. Giorgetti, G. Aquilanti, B. Ballarin, M. Berrettoni, M. C. Cassani, S. Fazzini, D. Nanni and D. Tonelli, Anal. Chem. 88 (2016) 6873-6880; [2] S. Fazzini, M. C. Cassani, B. Ballarin, E. Boanini, J. S. Girardon, A.S. Mamede, A. Mignani and D. Nanni, J. Phys. Chem. C. 118 (2014) 24538-24547; M. C. Cassani, B. Ballarin, D. Barreca, E. Boanini, E. Bonansegna, G. Carraro, S. Fazzini, A. Mignani, D. Nanni, D. Pinelli, RSC Adv. 6 (2016) 25780-25788; [3] B. Ballarin, D. Barreca, E. Boanini, M. C. Cassani, P. Dambruoso, A. Massi, A. Mignani, D. Nanni, C. Parise, A. Zaghi, ACS Sus. Chem. Eng. 5 (2017) 4746-4756