(1-bromoethenyl)(3,5,5-trimethylcyclohex-2-enyloxy)diisopropylsilane | 872352-53-9

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: (1-bromoethenyl)(3,5,5-trimethylcyclohex-2-enyloxy)diisopropylsilane
• 英文别名: 1-Bromoethenyl-di(propan-2-yl)-(3,5,5-trimethylcyclohex-2-en-1-yl)oxysilane
• CAS: 872352-53-9
• 化学式: C₁₇H₃₁BrOSi
• 分子量: 359.422
• InChiKey: GELVSCLBALNESR-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  6.35
• 重原子数：
  20
• 可旋转键数：
  5
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.76
• 拓扑面积：
  9.2
• 氢给体数：
  0
• 氢受体数：
  1

反应信息

• 作为反应物：
  描述：

  (1-bromoethenyl)(3,5,5-trimethylcyclohex-2-enyloxy)diisopropylsilane 在 三乙基硼 、 三正丁基氢锡 作用下， 以 正己烷 、 苯 为溶剂， 反应 24.0h， 以50%的产率得到2,2-diisopropyl-4,6,6-trimethyl-3-methyleneoctahydro-1,2-benzoxasilole
  参考文献：
  名称：

  1-Bromo-1-lithioethene:  A Practical Reagent in Organic Synthesis

  摘要：

  A reliable preparative scale synthesis of 1-bromo-1-lithioethene is reported. This reagent undergoes clean 1,2-addition with a range of aldehydes and ketones at -110 degrees C to afford the corresponding 2-bromo-1-alken-3-ols in moderate to excellent yield. Trapping with other electrophiles (acylsilanes, chlorosilanes, tributyltin chloride, iodine) cleanly provides practically useful yields of various 1-substituted 1-bromoethene products. Unexpectedly high diastereoselectivities were observed during the addition of 1-bromo-1-lithioethene to alpha-siloxy aldehydes (typically 10:1, Felkin-Ahn control) and protected ketopyranose and ketofuranose sugars (>= 10:1, addition from the less-hindered face). The title organolithium reagent possesses relatively low basicity at low temperature, and is compatible with a variety of common protecting groups. We believe that these unusual properties of 1-bronio-1-lithioethene may originate from the specific crystalline structure of the reagent in which lithium is coordinatively saturated and thus unavailable for chelation.

  DOI：

  10.1021/jo051125v
• 作为产物：
  描述：

  二异丙基二氯硅烷 在 咪唑 、 正丁基锂 、 lithium bromide 作用下， 以 四氢呋喃 、 乙醚 、 正戊烷 为溶剂， 反应 2.5h， 生成 (1-bromoethenyl)(3,5,5-trimethylcyclohex-2-enyloxy)diisopropylsilane
  参考文献：
  名称：

  1-Bromo-1-lithioethene:  A Practical Reagent in Organic Synthesis

  摘要：

  A reliable preparative scale synthesis of 1-bromo-1-lithioethene is reported. This reagent undergoes clean 1,2-addition with a range of aldehydes and ketones at -110 degrees C to afford the corresponding 2-bromo-1-alken-3-ols in moderate to excellent yield. Trapping with other electrophiles (acylsilanes, chlorosilanes, tributyltin chloride, iodine) cleanly provides practically useful yields of various 1-substituted 1-bromoethene products. Unexpectedly high diastereoselectivities were observed during the addition of 1-bromo-1-lithioethene to alpha-siloxy aldehydes (typically 10:1, Felkin-Ahn control) and protected ketopyranose and ketofuranose sugars (>= 10:1, addition from the less-hindered face). The title organolithium reagent possesses relatively low basicity at low temperature, and is compatible with a variety of common protecting groups. We believe that these unusual properties of 1-bronio-1-lithioethene may originate from the specific crystalline structure of the reagent in which lithium is coordinatively saturated and thus unavailable for chelation.

  DOI：

  10.1021/jo051125v

文献信息

• 1-Bromo-1-lithioethene:  A Practical Reagent in Organic Synthesis
  作者：Yehor Y. Novikov、Paul Sampson

  DOI：10.1021/jo051125v

  日期：2005.12.1

  A reliable preparative scale synthesis of 1-bromo-1-lithioethene is reported. This reagent undergoes clean 1,2-addition with a range of aldehydes and ketones at -110 degrees C to afford the corresponding 2-bromo-1-alken-3-ols in moderate to excellent yield. Trapping with other electrophiles (acylsilanes, chlorosilanes, tributyltin chloride, iodine) cleanly provides practically useful yields of various 1-substituted 1-bromoethene products. Unexpectedly high diastereoselectivities were observed during the addition of 1-bromo-1-lithioethene to alpha-siloxy aldehydes (typically 10:1, Felkin-Ahn control) and protected ketopyranose and ketofuranose sugars (>= 10:1, addition from the less-hindered face). The title organolithium reagent possesses relatively low basicity at low temperature, and is compatible with a variety of common protecting groups. We believe that these unusual properties of 1-bronio-1-lithioethene may originate from the specific crystalline structure of the reagent in which lithium is coordinatively saturated and thus unavailable for chelation.