rel-(2R,3S,6R)-2-carbomethoxy-6-methyl-3-propenyltetrahydropyran | 121223-27-6

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吡喃
• 英文名称: rel-(2R,3S,6R)-2-carbomethoxy-6-methyl-3-propenyltetrahydropyran
• CAS: 121223-27-6
• 化学式: C₁₁H₁₈O₃
• 分子量: 198.262
• InChiKey: ARAWEKCRHXPHRI-AEJSXWLSSA-N

反应信息

• 作为产物：
  描述：

  methyl 2-acetoxy-2-(6-methyl-5-hepten-2-oxy)acetate 在 四氯化锡 作用下， 以 二氯甲烷 为溶剂， 以63%的产率得到rel-(2R,3S,6R)-2-carbomethoxy-6-methyl-3-propenyltetrahydropyran
  参考文献：
  名称：

  π-Cyclizations of α-methoxycarbonyl oxycarbenium ions; synthesis of oxacyclic carboxylic esters

  摘要：

  Acid-mediated cyclization reactions are described of seven methyl 2-acetoxy-2-(3-alken-1-oxy)acetates with different chain substitution. The major product of the tin tetrachloride-induced cyclization reaction is in most cases a tetrahydropyran containing an equatorial carbomethoxy function at C2 and an axial chlorine atom at C4. The mechanism of its formation involves a net cis-addition of the intermediate alpha-ester oxycarbenium ion to the carbon-carbon double bond, most likely caused by a quasi axial orientation of the ester function in a chair-like transition state. The results are interpreted by invoking (1) the occurrence of a 2-oxonia-Cope rearrangement and (2) the participation of the ester function in the mechanism of cyclization by trapping the cyclic cationic intermediate. The cyclizations of two methyl 2-acetoxy-2-(4-alken-1-oxy)acetates and two methyl 2-acetoxy-2-(alkynoxy)acetates are also described .

  DOI：

  10.1016/s0040-4020(01)85238-8

文献信息

• Synthesis of oxacyclic carboxylic esters by way of methoxycarbonyloxonium ions; Evidence for a cationic oxa-cope rearrangement
  作者：Lucie D.M. Lolkema、Henk Hiemstra、Hendrik H. Mooiweer、W.Nico Speckamp

  DOI：10.1016/s0040-4039(00)82348-5

  日期：1988.1