不对称的乙烯化不激活的线性1,3-二烯的乙烯化
Rakesh K Sharma1, T V RajanBabu
1Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA.
用催化二烯的乙烯化有效地产生有价值的六-1,4-二烯. 配体选择和温度控制区域选择性和酶选择性,提供精确的合成控制.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 有机合成 有机合成
背景情况:
- 乙烯化是形成碳-碳键的关键反应.
- 在有机合成中,开发选择性和高效的乙烯催化剂仍然是一个重大挑战.
研究的目的:
- 通过使用催化剂,研究单位置换的乙烯基 (E) -1,3 -二烯的乙烯化.
- 探索连接体结构和反应温度对区域选择性和酶选择性的影响.
- 为了呈现预催化剂的固态结构.
主要方法:
- 使用双酸-CoCl(2) 复合物和三甲 (Me(3) Al) 的催化乙烯化.
- 不同的配体 (例如, (RR) -DIOP, (SS) -BDDP) 和反应温度 (例如,-45摄氏度).
- 分析区域选择性 (1,4-与1,2-加法) 和反选择性.
主要成果:
- 从单替代的1,3-dienes中有效合成 (Z) -3-alkylhexa-1,4-dienes.
- 在低温下通过特定的配体 (DIOP,BDDP) 实现高区域选择性和反抗选择性.
- 与Ni (II) 催化反应不同的是,以1-基替代的二烯主要产生Achiral线性1,4-添加产物.
结论:
- 双酸-CoCl(2) 复合物是二烯氧化的有效催化剂.
- 连接物和温度控制对于在催化氧化中实现高选择性至关重要.
- 这种方法为特定基质提供了与催化氧化相比独特的途径.
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