(4S)-4-[(3aS,6S,7aR)-6-methoxy-2,2-dimethyl-3a,6,7,7a-tetrahydro-1,3-benzodioxol-5-yl]-4-hydroxy-2,3-di(propan-2-yloxy)cyclobut-2-en-1-one | 188752-24-1

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: (4S)-4-[(3aS,6S,7aR)-6-methoxy-2,2-dimethyl-3a,6,7,7a-tetrahydro-1,3-benzodioxol-5-yl]-4-hydroxy-2,3-di(propan-2-yloxy)cyclobut-2-en-1-one
• CAS: 188752-24-1
• 化学式: C₂₀H₃₀O₇
• 分子量: 382.454
• InChiKey: OGTZBLMXZPYEGL-UJKGCTCZSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.23
• 重原子数：
  27.0
• 可旋转键数：
  6.0
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.75
• 拓扑面积：
  83.45
• 氢给体数：
  1.0
• 氢受体数：
  7.0

反应信息

• 作为反应物：
  描述：

  N-苄基-2-溴-N-甲基-2-丙烯-1-胺 、 (4S)-4-[(3aS,6S,7aR)-6-methoxy-2,2-dimethyl-3a,6,7,7a-tetrahydro-1,3-benzodioxol-5-yl]-4-hydroxy-2,3-di(propan-2-yloxy)cyclobut-2-en-1-one 在 叔丁基锂 作用下， 生成 (3aR,5bR,8aS,9aR,9bS)-8a-[(Benzyl-methyl-amino)-methyl]-5b-hydroxy-6,7-diisopropoxy-2,2-dimethyl-4,5b,8a,9,9a,9b-hexahydro-3aH-1,3-dioxa-cyclopenta[b]-as-indacen-8-one
  参考文献：
  名称：

  Evaluation of Amino Substituents as Nucleofugal Controllers of Regioselectivity and as Chelate Modulators of Stereoselectivity in Squarate Ester Cascades

  摘要：

  The tandem addition of an alkenyllithium reagent and a 2-lithioallylamine to squarate esters has been systematically examined. The effect of the sequencing of this twofold addition has been investigated. The extent to which the amino group is eliminated was found to be dependent on the structural features of the companion nucleophile. Also assessed was the comparative ease with which the amino and methoxy groups experience competitive beta-elimination from the highly reactive, medium-ring dianionic intermediates. Attempts were made to curtail the level of competing 1,4-addition, and success was achieved by increasing the effective size of the O-alkyl groups in the squarate ester. The highly stereocontrolled transformations described represent a notably direct means for producing highly fused polycyclic compounds, Mechanistic considerations sm rounding these reactions, which are characterized by an impressive enhancement of molecular scaffolding, are discussed.

  DOI：

  10.1021/jo9722919
• 作为产物：
  描述：

  (-)-(1S,6R)-3-Bromo-8,8-dimethyl-4-oxo-7,9-dioxabicyclo<4.3.0>non-2-ene 在 sodium tetrahydroborate 、 cerium(III) chloride 、 叔丁基锂 、 sodium hydride 作用下， 以 四氢呋喃 、 甲醇 为溶剂， 反应 14.25h， 生成 (4S)-4-[(3aS,6S,7aR)-6-methoxy-2,2-dimethyl-3a,6,7,7a-tetrahydro-1,3-benzodioxol-5-yl]-4-hydroxy-2,3-di(propan-2-yloxy)cyclobut-2-en-1-one
  参考文献：
  名称：

  Enhanced Channeling of the Squarate Cascade through the Dianionic Oxy-Cope Option. Oxy Substitution Markedly Augments Syn Delivery of the Second Alkenyllithium

  摘要：

  A general means for enhancing the extent to which squarate esters enter into cascade processes involving a dianionic oxy-Cope rearrangement as the key step is presented. Adoption of this sigmatropic process requires that the two alkenyllithium reagents being introduced add cis to each other, a kinetic bias which can be realized simply by the proper incorporation of ethereal oxygen substituents in the first organometallic reagent. Structural reorganization occurs via boat-like transition states such that stereoinduction manifests itself with high fidelity.

  DOI：

  10.1021/ja964140d