Catalytic production of hexane-1, 2, 5, 6-tetrol from bio-renewable levoglucosanol in water: effect of metal and acid sites on (stereo)-selectivity. Issue 19 (18th September 2018)

• Record Type: Journal Article
• Authors: Krishna, Siddarth H.; De bruyn, Mario; Schmidt, Zachary R.; Weckhuysen, Bert M.; Dumesic, James A.; Huber, George W.
• Is Part Of: Green chemistry. Volume 20:Issue 19(2018)
• Page Start: 4557
• Page End: 4565
• Publication Date: 2018-09-18
• Subjects: Environmental chemistry -- Industrial applications -- Periodicals; Environmental management -- Periodicals; 660
• DOI: 10.1039/c8gc02455c
• Languages: English
• ISSNs: 1463-9262

Abstract

Abstract : We report on a new route to produce hexane-1, 2, 5, 6-tetrol from cellulose-derived levoglucosanol using metal and acid catalysts. Abstract : We report on a new route to produce hexane-1, 2, 5, 6-tetrol (tetrol) from cellulose-derived levoglucosanol (lgol). We investigate the reaction intermediates formed over metal and acid catalysts, and propose a reaction network for this process. Lgol is converted to tetrol in up to 90% yield over a bifunctional Pt/SiO2 –Al2 O3 catalyst at 150 °C. High tetrol yields are maintained at lgol concentrations of up to 21 wt% in water. threo - and erythro -lgol first undergo hydrolysis to 3, 4-dideoxymannose (DDM) and 3, 4-dideoxyglucose (DDG), respectively. This reaction can be carried out selectively over an Amberlyst 70 acid catalyst at a temperature of 100 °C. At a higher temperature of 150 °C with no added catalyst, DDM and DDG undergo aldose–ketose isomerization to 3, 4-dideoxyfructose (DDF). DDM is hydrogenated to cis -tetrol over a Pt/SiO2 catalyst, while DDG is hydrogenated to trans -tetrol. Formation of DDF erases the stereocenter at the C2 position of lgol, and hydrogenation of DDF produces a nearly 1 : 1 mixture of cis - and trans -tetrol. This catalytic approach to produce tetrol from biomass opens the door to sustainable chemicals derived from tetrol.