(2R*,4R*)-4-acetamido-2-methoxy-4-methyltetrahydropyran | 109553-14-2

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 氧唑烯
• 英文名称: (2R*,4R*)-4-acetamido-2-methoxy-4-methyltetrahydropyran
• 英文别名: N-[(2S,4S)-2-methoxy-4-methyloxan-4-yl]acetamide
• CAS: 109553-14-2
• 化学式: C₉H₁₇NO₃
• 分子量: 187.239
• InChiKey: UNCNKPGPGIXJSN-IUCAKERBSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  0.1
• 重原子数：
  13
• 可旋转键数：
  2
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.89
• 拓扑面积：
  47.6
• 氢给体数：
  1
• 氢受体数：
  3

反应信息

• 作为产物：
  描述：

  3-甲基-3-丁烯-1-醇 、 乙腈 、 原甲酸三甲酯 在 四氯化锡 作用下， 反应 1.0h， 以77%的产率得到(2R*,4R*)-4-acetamido-2-methoxy-4-methyltetrahydropyran
  参考文献：
  名称：

  Chemistry of dioxenium cations. Synthetic and mechanistic studies on the stereocontrolled formation of tetrahydropyrans from homoallylic alcohols and ortho esters

  摘要：

  Despite their long history, dioxenium cations are underutilized reactive synthetic intermediates. It was found that ortho esters and homoallylic alcohols in the presence of Lewis acids provide 4-heterosubstituted pyranosides in a stereoselective manner. The mechanistic course of events was supported by control experiments and synthesis of a putative mixed ortho ester intermediate which exhibited identical reactivity. A transition state for termination of the dioxenium cation-olefin cyclization is proposed, involving intramolecular delivery of chloride by a coordinated tin species. Structure-reactivity relationships indicate that a cation-stabilizing substituent (alkyl or alkoxy) at the internal position of the olefin is required for cyclization. A variety of 3-alkyl-substituted homoallylic alcohols cyclize cleanly to substituted 2-alkoxytetrahydropyrans in good yield. beta-silyloxy silyl enol ethers were found to smoothly provide 4-oxotetrahydropyranosides when subjected to the same reaction conditions. For these substrates, the course of the cyclization proceeds in a different manner involving a rapid intermolecular Mukaiyama aldol condensation followed by transacetalization.

  DOI：

  10.1021/jo00021a043

文献信息

• Double Prins Cyclisation Enabled Rapid Access to α,ω‐Hydroxytetrahydropyrans
  作者：Jonathan Trevorrow、Anne O'Kearney‐McMullan、Lucie Miller Potucka、Adrian P. Dobbs

  DOI：10.1002/ejoc.202200810

  日期：2022.10.26

  substructure of many natural products and is frequently prepared through the oxidative cyclisation of a pendant hydroxyl group on to a pre-formed pyran. However access to such precursors has hitherto been challenging. A novel method for the preparation of hydroxydi- and hydroxytetrahydropyrans is reported utilizing a novel double-Prins cyclisation approach.

  螺缩酮部分是许多天然产物的重要子结构，通常通过将羟基侧基氧化环化到预先形成的吡喃上来制备。然而，迄今为止，获得此类前体一直具有挑战性。报道了一种制备羟基二和羟基四氢吡喃的新方法，该方法使用一种新的双 Prins 环化方法。
• PERTON, F.;ALBIZATI, KIM F., J. ORG. CHEM., 52,(1987) N 18, 4128-4130
  作者：PERTON, F.、ALBIZATI, KIM F.

  DOI：——

  日期：——