NMR Insights into the Unexpected Interaction of SnCl₄ with D-Glucosamine and Its Effect on 5-HMF Preparation in ZnCl₂ Molten Salt Hydrate Medium

TY - JOUR

T1 - NMR Insights into the Unexpected Interaction of SnCl4 with D-Glucosamine and Its Effect on 5-HMF Preparation in ZnCl2 Molten Salt Hydrate Medium

AU - Chen, Chunyan

AU - Ge, Wenzhi

AU - Jia, Lingyu

AU - Pedersen, Christian Marcus

AU - Yan , Qiao

AU - Jia, Shiyu

AU - Xiaoya , Guo

AU - Wang, Yingxiong

AU - Hou, Xianglin

PY - 2016/12/1

Y1 - 2016/12/1

N2 - SnCl4, a versatile Lewis acid catalyst in the biomass conversion, plays a positive role for the cellulose biomass conversion but negative for chitin biomass conversion as realized in our previous research. In this report, the unexpected effects of SnCl4 on the conversion of d-glucosamine (GlcNH2) to 5-hydroxymethylfurfural (5-HMF) in ZnCl2 molten salt hydrate medium were investigated. The strong interaction between SnCl4 and GlcNH2 in ZnCl2 molten salt hydrate medium was examined by nuclear magnetic resonance (NMR) techniques. Additionally the d-glucose and N-acetyl-d-glucosamine were also utilized in NMR titration experiments to reveal the complexation of amino group with Sn4+ ions during the catalytic process. The observed drifts of chemical shifts and signal broadening of the C2 position of GlcNH2 in 13C NMR spectra indicates that the amino group in GlcNH2 is probably the Sn4+ ion complexation site. The correlations in the 1H-15N HSQC NMR spectra provide the direct evidence and further confirm that the amino group is the complexation site between SnCl4 and GlcNH2. This very specific complex between the amino group and the Sn4+ ion inhibit the conversion of GlcNH2 to 5-HMF in ZnCl2 molten salt hydrate medium

AB - SnCl4, a versatile Lewis acid catalyst in the biomass conversion, plays a positive role for the cellulose biomass conversion but negative for chitin biomass conversion as realized in our previous research. In this report, the unexpected effects of SnCl4 on the conversion of d-glucosamine (GlcNH2) to 5-hydroxymethylfurfural (5-HMF) in ZnCl2 molten salt hydrate medium were investigated. The strong interaction between SnCl4 and GlcNH2 in ZnCl2 molten salt hydrate medium was examined by nuclear magnetic resonance (NMR) techniques. Additionally the d-glucose and N-acetyl-d-glucosamine were also utilized in NMR titration experiments to reveal the complexation of amino group with Sn4+ ions during the catalytic process. The observed drifts of chemical shifts and signal broadening of the C2 position of GlcNH2 in 13C NMR spectra indicates that the amino group in GlcNH2 is probably the Sn4+ ion complexation site. The correlations in the 1H-15N HSQC NMR spectra provide the direct evidence and further confirm that the amino group is the complexation site between SnCl4 and GlcNH2. This very specific complex between the amino group and the Sn4+ ion inhibit the conversion of GlcNH2 to 5-HMF in ZnCl2 molten salt hydrate medium

U2 - 10.1002/slct.201601237

DO - 10.1002/slct.201601237

M3 - Journal article

SN - 2365-6549

VL - 1

SP - 6540

EP - 6545

JO - ChemistrySelect

JF - ChemistrySelect

IS - 20

ER -