通过立体控制的催化交叉转化 Z 三位置换的α,β 不和和酸
Can Qin1,2, Tobias Koengeter1, Fengyue Zhao3
1Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States.
新的催化交叉转基因反应有效地产生具有高立体同位素纯度的Z-三替代. 这些转化利用复合物,为合成有价值的和酸提供广泛的基质范围.
科学领域:
- 有机化学
- 催化剂
- 有机金属化学
背景情况:
- 催化交叉转基因 (CM) 对于合成三替代基因至关重要,但范围和立体选择性往往有限.
- 在合成有机化学中产生高同位素纯度的Z-仍然是一个重大挑战.
研究的目的:
- 开发新型的催化交叉转基因反应,以合成具有高立体同位素纯度的Z-三替代.
- 扩大CM反应的范围,包括各种功能组如,醇和酸.
主要方法:
- 使用的 (Mo) 复合物,包括bis-aryloxide,monoaryloxide pyrrolide和monoaryloxide chloride变种.
- 用于实际应用的含有Mo复合物的空气稳定片.
- 研究的基质范围与基,基和基碳酸,基和酸化物.
主要成果:
- 实现了Z-三替代α-甲基,α,β-不和,基和基,醇和酸的高效合成.
- 获得高产率 (55-95%) 和优异的Z/E比率 (通常>95:5,范围为88:12至98:2).
- 通过两步合成异敏乳前体和单步转化兰酸的证明适用性.
结论:
- 开发的CM反应为合成有价值的Z-三替代提供了多功能和立体选择性方法.
- 密度功能理论 (DFT) 的研究表明,一个被取代的Mo基烯重新进入CM循环是活性的关键.
- 金属循环布坦形成 (CM) 和崩 (homo-metathesis) 的相对能量障碍决定了CM或homo-metathesis的优势.
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