TY - JOUR
T1 - Microwave-heated γ-Alumina Applied to the Reduction of Aldehydes to Alcohols
AU - Dhokale, Bhausaheb
AU - Susarrey-Arce, Arturo
AU - Pekkari, Anna
AU - Runemark, August
AU - Moth-Poulsen, Kasper
AU - Langhammer, Christoph
AU - Härelind, Hanna
AU - Busch, Michael
AU - Vandichel, Matthias
AU - Sundén, Henrik
N1 - Publisher Copyright:
© 2020 The Authors. Published by Wiley-VCH GmbH
PY - 2020/12/16
Y1 - 2020/12/16
N2 - The development of cheap and robust heterogeneous catalysts for the Meerwein-Ponndorf-Verley (MPV) reduction is desirable due to the difficulties in product isolation and catalyst recovery associated with the traditional use of homogeneous catalysts for MPV. Herein, we show that microwave heated γ-Al2O3 can be used for the reduction of aldehydes to alcohols. The reaction is efficient and has a broad substrates scope (19 entries). The products can be isolated by simple filtration, and the catalyst can be regenerated. With the use of microwave heating, we can direct the heating to the catalyst rather than to the whole reaction medium. Furthermore, DFT was used to study the reaction mechanism, and we can conclude that a dual-site mechanism is operative where the aldehyde and 2-propoxide are situated on two adjacent Al sites during the reduction. Additionally, volcano plots were used to rationalize the reactivity of Al2O3 in comparison to other metal oxides.
AB - The development of cheap and robust heterogeneous catalysts for the Meerwein-Ponndorf-Verley (MPV) reduction is desirable due to the difficulties in product isolation and catalyst recovery associated with the traditional use of homogeneous catalysts for MPV. Herein, we show that microwave heated γ-Al2O3 can be used for the reduction of aldehydes to alcohols. The reaction is efficient and has a broad substrates scope (19 entries). The products can be isolated by simple filtration, and the catalyst can be regenerated. With the use of microwave heating, we can direct the heating to the catalyst rather than to the whole reaction medium. Furthermore, DFT was used to study the reaction mechanism, and we can conclude that a dual-site mechanism is operative where the aldehyde and 2-propoxide are situated on two adjacent Al sites during the reduction. Additionally, volcano plots were used to rationalize the reactivity of Al2O3 in comparison to other metal oxides.
KW - Microwave-assisted catalysis
KW - MPV reduction
KW - γ-AlO
UR - http://www.scopus.com/inward/record.url?scp=85093839878&partnerID=8YFLogxK
U2 - 10.1002/cctc.202001284
DO - 10.1002/cctc.202001284
M3 - Article
AN - SCOPUS:85093839878
SN - 1867-3880
VL - 12
SP - 6344
EP - 6355
JO - ChemCatChem
JF - ChemCatChem
IS - 24
ER -