以溴化1-（2，3，4，6-四-O-乙酰基-β-D-吡喃葡萄糖基）-3-丁基咪唑盐（化合物1）、吡啶和醋酸钯为原料，快速合成了空气稳定的1-（2，3，4，6-四-O-乙酰基-β-D-吡喃葡萄糖基）-3-丁基-咪唑-2-亚基]-溴化钯（II）-吡啶（配合物2）.配合物2的结构中存在乙酰基-β-D-吡喃葡萄糖基，糖环上有多个手性碳，其核磁共振氢谱（1H NMR）和碳谱（13C NMR）较复杂，不易归属.本文通过元素分析对配合物2的组成进行表征，运用1D和2D NMR技术（包括1H NMR、13C NMR、DEPT135、DEPT90、DEPT45、COSY、1H-13C HSQC、1H-13C HMBC）对配合物2的1H和13C NMR信号进行全归属.研究发现，在乙酰基-β-D-吡喃葡萄糖基的稠环上多个弱配位的氧和乙酰基氧原子上孤电子对的作用下，配合物2的氮杂环卡宾-钯（II）-吡啶金属键形成对稠环上碳氢化学环境的影响比对丁基的影响更为明显.
周中高
,
谢倩
,
元洋洋
,
李静
,
路东亮
,
陈正旺
. 吡喃葡糖基氮杂环卡宾-钯(II)-吡啶配合物的NMR研究[J]. 波谱学杂志, 2020
, 37(4)
: 505
-514
.
DOI: 10.11938/cjmr20202806
A new air-stable and easy-to-handle 1-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)-3-butyl-imidazol-2-ylidene] Pd(pyridine)Br2 (complex 2) was synthesized from the imidazolium halide salts 1-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)-3-butyl-midazolium bromide (compound 1) by reaction with Pd(OAc)2 in pyridine. Complex 2 contains multiple chiral centers on the sugar ring. The molecular structures of complex 2 were determined with elemental analysis and liquid-state nuclear magnetic resonance (NMR) spectra. 1H and 13C chemical shifts of complex 2 were fully assigned. It was found that the effects of the carbon and proton chemical environment on the sugar ring is more obvious than that on the butyl chain after formation of N-heterocyclic carbene-palladium(II)-pyridine (NHCs-Pd(II)-Py)-metal bond in the presence of multiple weakly coordinated oxygen.
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