title: Selective Conversion of 5-Hydroxymethylfuraldehyde Using Cp*Ir Catalysts in Aqueous Formate Buffer Solution.
abstract: The highly selective hydrogenation/hydrolytic ring-opening reaction of 5-hydroxymethylfuraldehyde (5-HMF) was catalyzed by homogeneous Cp*Ir(III) half-sandwich complexes to produce 1-hydroxy-2,5-hexanedione (HHD). Adjustment of pH was found to regulate the distribution of products and reaction selectivity, and full conversion of 5-HMF to HHD with 99 % selectivity was achieved at pH 2.5. A mechanistic study revealed that the hydrolysis/ring-opening reaction of 2,5-bis-(hydroxymethyl)furan is the important intermediate reaction step. In addition, an isolated yield of 85 % for HHD was obtained in a 10 g-scale experiment, and the reaction with fructose as the starting material also led to a 98 % GC yield (71.9 % to fructose) of HHD owing to the excellent tolerance of the catalyst under acidic conditions.
authors.affiliation: iChEM, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China.
authors.forename: Wei-Peng
authors.initials: WP
authors.lastname: Wu
authors.affiliation: iChEM, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China.
authors.forename: Yong-Jian
authors.initials: YJ
authors.lastname: Xu
authors.affiliation: iChEM, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhu
authors.affiliation: iChEM, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China.|Nano Science and Technology Institute, University of Science and Technology of China, Suzhou, 215123, P. R. China.
authors.forename: Min-Shu
authors.initials: MS
authors.lastname: Cui
authors.affiliation: iChEM, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China.|School of Medical Engineering and, Key Laboratory of Advanced Functional Materials and Devices, Hefei University of Technology, Hefei, 230009, P. R. China.
authors.forename: Xing-Long
authors.initials: XL
authors.lastname: Li
authors.affiliation: iChEM, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China. dengjin@ustc.edu.cn.
authors.forename: Jin
authors.initials: J
authors.lastname: Deng
authors.affiliation: iChEM, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China. fuyao@ustc.edu.cn.
authors.forename: Yao
authors.initials: Y
authors.lastname: Fu
mesh_terms: D002021:Buffers; D002384:Catalysis; D005561:Formates / Q000737:chemistry*; D005662:Furaldehyde / Q000031:analogs & derivatives* / Q000737:chemistry; D006588:Hexanones / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007495:Iridium / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D012996:Solutions; D014867:Water / Q000737:chemistry*
chemical_list: D002021:Buffers; D005561:Formates; D006588:Hexanones; D009942:Organometallic Compounds; D012996:Solutions; D014867:Water; C030544:formic acid; D007495:Iridium; C008046:5-hydroxymethylfurfural; C011269:2,5-hexanedione; D005662:Furaldehyde
keywords: 5-hmf; biomass; homogeneous catalysis; iridium; ring-opening