TY - JOUR
T1 - Novel organotin-PTA complexes supported on mesoporous carbon materials as recyclable catalysts for solvent-free cyanosilylation of aldehydes
AU - Mahmoud, Abdallah G.
AU - Librando, Ivy L.
AU - Paul, Anup
AU - Carabineiro, Sónia A.C.
AU - Ferraria, Ana Maria
AU - Botelho do Rego, Ana Maria
AU - Guedes da Silva, M. Fátima C.
AU - Geraldes, Carlos F.G.C.
AU - Pombeiro, Armando J.L.
N1 - Publisher Copyright:
© 2023 Elsevier B.V.
PY - 2023/11/1
Y1 - 2023/11/1
N2 - New organotin compounds with general formula [(PTA-CH2-C6H4-p-COO)SnR3]Br (where R is Me for 3 and Ph for 4; PTA = 1,3,5-triaza-7-phosphaadamantane), bearing the methylene benzoate PTA derivative, were synthesized through a mild two-step process. The compounds were characterized by Fourier transform infrared spectroscopy, electrospray ionization mass spectrometry, elemental analysis and nuclear magnetic resonance spectroscopy (NMR). They were heterogenized on commercially available activated carbon (AC) and multi-walled carbon nanotubes (CNT), as well as on their chemically modified analogues. The obtained materials were characterized by scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. Complex 3 supported on activated carbon (3-AC) was found to be an active and recyclable catalyst for the cyanosilylation of several aromatic and aliphatic aldehydes. Using 3-AC with a low loading of 0.1 mol% several substrates were quantitatively converted, within just 5 min at 50 °C and under microwave irradiation in solvent-free conditions. Multinuclear NMR analysis suggested a mechanism that potentially involves a double activation process, where the nucleophilic phosphorus at the PTA derivative acts as a Lewis base and the Sn(IV) metal centre as a Lewis acid.
AB - New organotin compounds with general formula [(PTA-CH2-C6H4-p-COO)SnR3]Br (where R is Me for 3 and Ph for 4; PTA = 1,3,5-triaza-7-phosphaadamantane), bearing the methylene benzoate PTA derivative, were synthesized through a mild two-step process. The compounds were characterized by Fourier transform infrared spectroscopy, electrospray ionization mass spectrometry, elemental analysis and nuclear magnetic resonance spectroscopy (NMR). They were heterogenized on commercially available activated carbon (AC) and multi-walled carbon nanotubes (CNT), as well as on their chemically modified analogues. The obtained materials were characterized by scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. Complex 3 supported on activated carbon (3-AC) was found to be an active and recyclable catalyst for the cyanosilylation of several aromatic and aliphatic aldehydes. Using 3-AC with a low loading of 0.1 mol% several substrates were quantitatively converted, within just 5 min at 50 °C and under microwave irradiation in solvent-free conditions. Multinuclear NMR analysis suggested a mechanism that potentially involves a double activation process, where the nucleophilic phosphorus at the PTA derivative acts as a Lewis base and the Sn(IV) metal centre as a Lewis acid.
KW - 1,3,5-triaza-7-phosphaadamantane
KW - Carbon materials
KW - Cyanosilylation
KW - Heterogeneous catalysis
KW - Microwave
KW - Tetrel σ-hole bond
UR - https://www.scopus.com/pages/publications/85163142298
U2 - 10.1016/j.cattod.2023.114270
DO - 10.1016/j.cattod.2023.114270
M3 - Article
AN - SCOPUS:85163142298
SN - 0920-5861
VL - 423
JO - Catalysis Today
JF - Catalysis Today
M1 - 114270
ER -