1,2,6-O-(4-Methoxyorthobenzoyl)-β-D-mannopyranose | 134593-77-4

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯酚醚
• 英文名称: 1,2,6-O-(4-Methoxyorthobenzoyl)-β-D-mannopyranose
• CAS: 134593-77-4
• 化学式: C₁₄H₁₆O₇
• 分子量: 296.277
• InChiKey: NIKZWRHXPLXHBI-CZDMEZMVSA-N

反应信息

• 作为产物：
  描述：

  1,2-O-(α-exo,4-Dimethoxybenzylidene)-β-mannopyranose 在 氘代盐酸 作用下， 以 氘代乙腈 、 重水 为溶剂， 生成 1,2,6-O-(4-Methoxyorthobenzoyl)-β-D-mannopyranose
  参考文献：
  名称：

  An investigation of intermediates in the hydrolysis of ortho esters derived from D-glucose and D-mannose

  摘要：

  The hydrolysis of a series of 1,2-ortho esters derived from alpha-D-glucopyranose and beta-D-mannopyranose have been investigated by NMR and UV spectroscopy. When the hydrolysis of 1,2-O-(1-exo-ethoxyethylidene)-alpha-D-glucopyranose (6) in CD3CN (97.2 v %) and D2O (2.8 v %) containing DCl (2.8 x 10(-4) M) was followed by H-1 NMR spectroscopy, an intermediate was detected that may be the corresponding hemi ortho ester. Evidence was also obtained for the incursion of a hemi ortho ester in the hydrolysis of 1,2-O-(alpha-exo,4-dimethoxy-benzylidene)-alpha-D-glucopyranose (14) under similar conditions. The proportions of the hydrolysis products of 6, 1-O-acetyl-alpha-D-glucopyranose (13), and 2-O-acetyl-alpha-D-glucopyranose (12) depend on acid concentration with more of the former being formed at the higher acid concentrations. When the hydrolysis of 14 was studied at higher acid concentrations (DCl, 0.17 M) the intermediate cation 15 was detected. Evidence was obtained by O-18-labeled studies for decomposition of this by attack of water at C-1 of the glucopyranose ring and by an attack at the pro-acyl carbon of the dioxolanylium ion depending on the reaction conditions. In the hydrolysis of the ortho esters derived from beta-D-mannopyranose, tricyclic 1,2,6-ortho esters were detected in solvents of low water content and when the concentration of DCl was 0.33 M, the intermediate cation was also detected. The kinetics of hydrolysis of the two series of ortho esters were studied by UV spectrophotometry, and evidence was obtained that the 1,2-O-(alpha-exo-alkoxy-4-methoxybenzylidene)-alpha-D-glucopyranoses reacted with rate-limiting breakdown of intermediate hemi ortho ester at high acid concentrations. Evidence for similar behavior was obtained for the hydrolysis of the analogous glucose orthobenzoate esters and mannose 4-methoxyorthobenzoate esters, but the other compounds studied showed no evidence for a change in the rate-determining step of their hydrolyses or else showed complex kinetics on hydrolysis indicative that formation and breakdown of the hemi ortho ester were proceeding at comparable rates.

  DOI：

  10.1021/jo00014a018