在内部 π 键上启动的有用的催化 enantioselective 阴离子双解消反应:方法和应用
Karavadhi Surendra1, Goreti Rajendar, E J Corey
1Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States.
一种新型的催化方法使用二-BINOL-抗五化物复合物进行反选择性阴离子多环化. 这种方法有效地从内部π键中合成了包括天然产品在内的奇拉多环分子.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 不对称的合成方法
背景情况:
- 酵素选择性合成对于生产性分子,特别是天然产品和药品至关重要.
- 为复杂的多环结构开发高效的催化方法仍然是有机化学的一个重大挑战.
研究的目的:
- 扩大对内 π 键的异选择性聚环化的应用.
- 展示一种强大而通用的方法来构建性多环框架.
- 为有价值的天然产品及其类似物提供简化合成路线.
主要方法:
- 使用1:1复合的o,o'-二-R-BINOL和五化物 (SbCl5) 作为催化剂.
- 研究了具有终端和内部π键的多不和基质的酶选择性阴离子多环化.
- 开发了直接的合成途径到dysideapalaunic酸,脱酸,和epipodocarpic酸.
主要成果:
- 成功地证明了催化系统在内部π键上进行酶选择性多环化的能力.
- 在形成奇拉多环分子中取得了可预测的立体化学结果.
- 提供高效和简短的合成路线以准天然产品和相关化合物.
结论:
- 开发的方法通过允许使用内部π键,显著扩大了酶选择性阴离子聚环化范围.
- 这种方法为快速构建多种多循环结构提供了一个强大的策略.
- 合成的dysideapalaunic酸,脱酸,和epipodocarpic酸突出了这个enantioselective方法的实际实用性和价值.
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