通过顺序的α-/β-C-H功能化转型烯的复杂聚烯的立体选择性合成
Yuhang Zhu1, Yini Wang1, Wenzhou Shen1
1College of Materials, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou, 311121, Zhejiang, China.
这项研究引入了一种新的化辅助方法,用于E-styrenes的顺序C-H功能化. 该过程实现了高产量和选择性,在创建多样化的1,3-二烯和1,3,5-三烯方面.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 合成方法论 合成方法论
背景情况:
- 序列C-H功能化为分子复杂性提供了一个强大的途径.
- 开发用于功能化多重C-H键的选择性方法仍然是有机合成的一个关键挑战.
研究的目的:
- 报告第一个以化辅助的E-styrenes的序列α-/β-C-H功能化.
- 建立一种用于合成高度置换的1,3-二烯和1,3,5-三烯的多功能协议.
主要方法:
- 使用了pyrazinamide作为一种合导向组.
- 采用催化剂进行序列α-和β-C-H功能化.
- 通过机械实验和DFT计算,研究了反应机制.
主要成果:
- 在α-C-H功能化 (exo-cyclopalladation) 和β-C-H功能化 (endo-cyclopalladation) 中获得了优异的区域和立体选择性.
- 合成了三和四替代的1,3-二烯和四和五替代的1,3,5-三烯,产量高达97%,具有高的E/Z选择性 (>99/1).
- 证明了广泛的功能组耐受性,可扩展性 (克尺度),以及适用于一和两步合成.
结论:
- 开发的协议为构建复杂的二烯和三烯提供了一种高效和多功能方法.
- 化辅助对于以高选择性指导序列性C-H功能化至关重要.
- 这些发现扩大了合成结构多样化的有机分子的工具包.
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