(R)-2-(tert-Butyl-dimethyl-silanyloxy)-1,2-bis-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl)-ethanone | 189701-52-8

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: (R)-2-(tert-Butyl-dimethyl-silanyloxy)-1,2-bis-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl)-ethanone
• 英文别名: (2R)-2-[tert-butyl(dimethyl)silyl]oxy-1,2-bis[(4R)-2,2-dimethyl-1,3-dioxolan-4-yl]ethanone
• CAS: 189701-52-8
• 化学式: C₁₈H₃₄O₆Si
• 分子量: 374.55
• InChiKey: BDEKSLXIKDDPJC-UMVBOHGHSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.25
• 重原子数：
  25
• 可旋转键数：
  6
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.94
• 拓扑面积：
  63.2
• 氢给体数：
  0
• 氢受体数：
  6

反应信息

• 作为反应物：
  描述：

  乙基溴化镁 、 (R)-2-(tert-Butyl-dimethyl-silanyloxy)-1,2-bis-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl)-ethanone 以 四氢呋喃 为溶剂， 反应 0.25h， 生成 (1R,2S)-1-(tert-Butyl-dimethyl-silanyloxy)-1,2-bis-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl)-butan-2-ol 、 (1R,2R)-1-(tert-Butyl-dimethyl-silanyloxy)-1,2-bis-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl)-butan-2-ol
  参考文献：
  名称：

  Diastereoselective Grignard Additions to O-Protected Polyhydroxylated Ketones:  A Reaction Controlled by Groundstate Conformation?

  摘要：

  The O-protected polyhydroxy ketones 9-14 and 39, 42 add sigma-type Grignard reagents with >90:10 stereoselectivity to give the 3,4-syn-adducts 17-28 and 43, 45, respectively, as the major diastereomers (Tables 1 and 2). The stereoselectivity is interpreted in terms of early transition states which are very close to the groundstate conformations shown in Figure 6 and 7. These demonstrate that the ''top face'' of the carbonyl group is much less shielded than the ''bottom'' face. Complexation phenomena are of minor importance. It is also shown that the classical transition state models (Felkin-Anh or chelate Cram) are not applicable to polyoxygenated ketones.

  DOI：

  10.1021/jo961542v
• 作为产物：
  描述：

  (1R,2S)-2-[tert-butyl(dimethyl)silyl]oxy-1,2-bis[(4R)-2,2-dimethyl-1,3-dioxolan-4-yl]ethanol 在 草酰氯 、 TEA 、 二甲基亚砜 作用下， 以 二氯甲烷 为溶剂， 以91%的产率得到(R)-2-(tert-Butyl-dimethyl-silanyloxy)-1,2-bis-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl)-ethanone
  参考文献：
  名称：

  Diastereoselective Grignard Additions to O-Protected Polyhydroxylated Ketones:  A Reaction Controlled by Groundstate Conformation?

  摘要：

  The O-protected polyhydroxy ketones 9-14 and 39, 42 add sigma-type Grignard reagents with >90:10 stereoselectivity to give the 3,4-syn-adducts 17-28 and 43, 45, respectively, as the major diastereomers (Tables 1 and 2). The stereoselectivity is interpreted in terms of early transition states which are very close to the groundstate conformations shown in Figure 6 and 7. These demonstrate that the ''top face'' of the carbonyl group is much less shielded than the ''bottom'' face. Complexation phenomena are of minor importance. It is also shown that the classical transition state models (Felkin-Anh or chelate Cram) are not applicable to polyoxygenated ketones.

  DOI：

  10.1021/jo961542v

文献信息

• Diastereoselective Grignard Additions to <i>O</i>-Protected Polyhydroxylated Ketones:  A Reaction Controlled by Groundstate Conformation?
  作者：Johann Mulzer、Catarina Pietschmann、Jürgen Buschmann、Peter Luger

  DOI：10.1021/jo961542v

  日期：1997.6.13

  The O-protected polyhydroxy ketones 9-14 and 39, 42 add sigma-type Grignard reagents with >90:10 stereoselectivity to give the 3,4-syn-adducts 17-28 and 43, 45, respectively, as the major diastereomers (Tables 1 and 2). The stereoselectivity is interpreted in terms of early transition states which are very close to the groundstate conformations shown in Figure 6 and 7. These demonstrate that the ''top face'' of the carbonyl group is much less shielded than the ''bottom'' face. Complexation phenomena are of minor importance. It is also shown that the classical transition state models (Felkin-Anh or chelate Cram) are not applicable to polyoxygenated ketones.