基酸盐,基和基的三组合合反应:一种化学选择性的单阶段糖酸醇结构
David A Nicewicz1, Jeffrey S Johnson
1Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, USA.
Journal of the American Chemical Society
|April 28, 2005
概括
一种新的一反应有效地从简单的原料中合成受保护的1,2-二醇. 这种方法为复杂分子提供了一条通往复杂分子的多功能途径,以良好的效率产生高度功能化的产品.
科学领域:
- 有机化学 有机化学
- 合成化学 合成化学
- 催化剂是一种催化剂.
背景情况:
- 开发高效的合成方法对于访问复杂的有机分子至关重要.
- 三组件合反应提供了原子经济,并简化了合成途径.
- 保护组策略对于多功能化合物的多步合成至关重要.
研究的目的:
- 开发一种新型的一,三组分反应,用于合成功能密集的西保护型糖酸醇.
- 为了建立一个随后的去保护/催化序列,以产生完全受保护的1,2-二醇.
- 探索与各种终端和化物反应的范围和局限性.
主要方法:
- 一个单,三组件合反应,涉及西基酸盐,终端酸盐和化物.
- 使用化 (ZnI2) 和三乙 (Et3N) 作为催化剂和基础.
- 进行了随后的单去保护和化序列,以产生乙胺.
主要成果:
- 在良好的产量中成功合成了西里尔保护的糖酸二醇 (2).
- 通过单序列实现转化为完全受保护的1,2-二醇 (乙胺,3).
- 证明了反应的多功能性与一系列的终端基和基,产生适度的 diastereoselectivities.
- 机理学研究表明,乙化和基酸盐之间的化学选择反应.
- 一个未经优化的性系统产生了具有良好的二聚体选择性 (89:11 dr) 的酶体丰富添加物 (64% ee).
结论:
- 提出的方法提供了一个高效和多功能途径,高功能,受保护的1,2-二醇.
- 反应的单性质提高了合成效率和原子经济.
- 这种反应显示出不对称合成的潜力,并进行进一步的优化.
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