methyl β-<(1S,3S)-3-isopropyl-1-methyl-2-oxocyclopentyl>-2,5,5-trimethyl-1,3-dioxane-(2R)-valerate | 131973-37-0

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: methyl β-<(1S,3S)-3-isopropyl-1-methyl-2-oxocyclopentyl>-2,5,5-trimethyl-1,3-dioxane-(2R)-valerate
• CAS: 131973-37-0
• 化学式: C₂₂H₃₈O₅
• 分子量: 382.541
• InChiKey: LNXHMNAUEIWMRU-WURXZWLQSA-N

反应信息

• 作为产物：
  描述：

  3-((1S,3S)-2-Hydroxy-3-isopropyl-1-methyl-cyclopentyl)-5-(2,5,5-trimethyl-[1,3]dioxan-2-yl)-pentanoic acid methyl ester 在 重铬酸吡啶 、 3 A molecular sieve 作用下， 以 二氯甲烷 为溶剂， 反应 4.0h， 生成 methyl β-<(1S,3S)-3-isopropyl-1-methyl-2-oxocyclopentyl>-2,5,5-trimethyl-1,3-dioxane-(2R)-valerate
  参考文献：
  名称：

  Synthetic studies on basmane diterpenes. Enantiospecific total synthesis of (+)-7,8-epoxy-2-basmen-6-one by Claisen ring expansion

  摘要：

  The first synthesis of an epoxybasmenone is described. The enantiospecific pathway begins by transforming optically pure aldehyde 10 into bicyclic lactone 39. Methylenation of 39 by means of the Tebbe reaction allows for operation of a Claisen rearrangement that proceeds almost completely by way of chair transition state 44 to give the cyclooctadienone 42. Regiospecific cyclopentannulation with installation of four additional stereogenic centers rested upon successful introduction of a functionalized four-carbon chain as in 48, facially controlled hydrogenation of the conjugated double bond, cyclization, and hydroxyl-directed epoxidation. Finally, Swern oxidation led to the target molecule 3, whose three-dimensional structural features were confirmed by X-ray crystallography.

  DOI：

  10.1021/ja00007a039