Accelerated decarbonylation of 5-hydroxymethylfurfural in compressed carbon dioxide: a facile approach. Issue 10 (26th April 2018)

• Record Type: Journal Article
• Authors: Chatterjee, Maya; Ishizaka, Takayuki; Kawanami, Hajime
• Is Part Of: Green chemistry. Volume 20:Issue 10(2018)
• Page Start: 2345
• Page End: 2355
• Publication Date: 2018-04-26
• Subjects: Environmental chemistry -- Industrial applications -- Periodicals; Environmental management -- Periodicals; 660
• DOI: 10.1039/c8gc00174j
• Languages: English
• ISSNs: 1463-9262

Abstract

Abstract : The high efficiency of compressed CO2 in combination with a metal catalyst was successfully demonstrated in the decarbonylation of HMF. Abstract : Herein, decarbonylation of biomass-based 5-hydroxymethylfurfural (HMF) in compressed CO2 with an unexpected acceleration of the reaction rate and excellent catalytic activity is reported. Without any additive, CO surrogates, or any organic solvents, via the developed method, an excellent conversion of 99.8% and highest selectivity of furfuryl alcohol (99.6%) in 4 h at 145 °C were achieved using an alumina-supported Pd catalyst (Pd/Al2 O3 ). The superior activity is due to the unique characteristics (miscibility of reactant gases and high diffusivity) of compressed CO2 and the synergy between CO2 and Pd/Al2 O3, where CO2 plays an interesting role in accelerating the reaction by enhancing the diffusion of CO and furfuryl alcohol (both products have high solubilities in CO2 ), consequently shifting the equilibrium to the forward direction. Characterisation of the catalyst suggested its direct interaction with the substrate and provided an indication of the possible reaction path. Thus, a mechanism was outlined. Compared to the results obtained using organic solvents, the results obtained using compressed CO2 were superior in terms of activity, selectivity, and reaction rate. This strategy highlights easy product separation, improved catalyst life, and a simple sustainable process. The efficiency of this protocol is confirmed by its potential application to a series of aldehydes with various substituents to produce decarbonylated products in good to excellent yields.