(1S)-(+)-1α-acetoxy-2α,3β-dibromo-4α-hydroxycyclohexane | 132513-01-0

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: (1S)-(+)-1α-acetoxy-2α,3β-dibromo-4α-hydroxycyclohexane
• 英文别名: [(1S,2S,3S,4R)-2,3-dibromo-4-hydroxycyclohexyl] acetate
• CAS: 132513-01-0
• 化学式: C₈H₁₂Br₂O₃
• 分子量: 315.989
• InChiKey: SKTWBBUFUOZEOV-KVPKETBZSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.7
• 重原子数：
  13
• 可旋转键数：
  2
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.88
• 拓扑面积：
  46.5
• 氢给体数：
  1
• 氢受体数：
  3

反应信息

• 作为产物：
  描述：

  cis-2-cyclohexenyl-1,4-diacetate 在 溴 作用下， 以 二硫化碳 、 水 为溶剂， 反应 72.83h， 生成 (1S)-(+)-1α-acetoxy-2α,3β-dibromo-4α-hydroxycyclohexane
  参考文献：
  名称：

  A rule to predict which enantiomer of a secondary alcohol reacts faster in reactions catalyzed by cholesterol esterase, lipase from Pseudomonas cepacia, and lipase from Candida rugosa

  摘要：

  The enantioselectivity of the title enzymes for more than 130 esters of secondary alcohols is correlated by a rule based on the sizes of the substituents at the stereocenter. This rule predicts which enantiomer of a racemic secondary alcohol reacts faster for 14 of 15 substrates of cholesterol esterase (CE), 63 of 64 substrates of lipase from Pseudomonas cepacia (PCL), and 51 of 55 cyclic substrates of lipase from Candida rugosa (CRL). The enantioselectivity of CRL for acyclic secondary alcohols is not reliably predicted by this rule. This rule implies that the most efficiently resolved substrates are those having substituents which differ significantly in size. This hypothesis was used to design syntheses of two chiral synthons: esters of (R)-lactic acid and (S)-(-)-4-acetoxy-2-cyclohexen-1-one, 70. As predicted, the acetate group of the methyl ester of lactyl acetate was hydrolyzed by PCL with low enantioselectivity because the two substituents, CH3 and C(O)OCH3, are similar in size. To improve the enantioselectivity, the methyl ester was replaced by a tert-butyl ester. The acetate group of the tert-butyl ester of lactyl acetate was hydrolyzed with high enantioselectivity (E > 50). Enantiomerically pure (R)-(+)-tert-butyl lactate (> 98% ee, 6.4 g) was prepared by kinetic resolution. For the second example, low enantioselectivity (E < 3) was observed in the hydrolysis of cis-1,4-diacetoxycyclohex-2-ene, a meso substrate where the two substituents, CH2CH2 and CH = CH, are similar in size. To improve enantioselectivity, the size of the CH = CH substituent was increased by addition of Br2. The new substrate was hydrolyzed with high enantioselectivity (E > 65) using either CE or CRL. Enantiomerically pure 70 (98% ee) was obtained after removal of the bromines with zinc and oxidation with CrO3/pyridine.

  DOI：

  10.1021/jo00008a016

文献信息

• Synthetic Studies toward the Construction of the <i>cis</i>-Decalin Portion of Superstolides A and B. Application of a Sequential Double Michael Reaction and an Anionic Oxy-Cope Rearrangement
  作者：Zhengmao Hua、Wensheng Yu、Mei Su、Zhendong Jin

  DOI：10.1021/ol050339w

  日期：2005.5.1

  A highly convergent strategy for the asymmetric synthesis of the cis-decalin portion of the antitumor macrolide superstolide A was developed. The key reactions in our approach involve a sequential double Michael reaction and an anionic oxy-Cope rearrangement.

  针对抗肿瘤大环内酯类超环氧化物A的顺式十氢化萘部分的不对称合成，提出了一种高度收敛的策略。我们方法中的关键反应包括连续的双迈克尔反应和阴离子氧基-Cope重排。