当前位置: X-MOL 学术J. Am. Chem. Soc. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Organocatalyzed Birch Reduction Driven by Visible Light
Journal of the American Chemical Society ( IF 14.4 ) Pub Date : 2020-07-14 , DOI: 10.1021/jacs.0c05899
Justin P Cole 1 , Dian-Feng Chen 1 , Max Kudisch 1 , Ryan M Pearson 1 , Chern-Hooi Lim 2 , Garret M Miyake 1
Affiliation  

The Birch reduction is a powerful synthetic methodology that uses solvated electrons to convert inert arenes to 1,4-cyclohexadienes-valuable intermediates for building molecular complexity. Birch reductions traditionally employ alkali metals dissolved in ammonia to produce a solvated electrons for the reduction of unactivated arenes such as benzene (Ered < -3.42 V vs. SCE). Photoredox catalysts have been gaining popularity in highly-reducing applications, but none have been reported to demonstrate reduction potentials powerful enough to reduce benzene. Here, we introduce benzo[ghi]perylene imides as new organic photoredox catalysts for Birch reductions performed at ambient temperature and driven by visible light from commercially available LEDs. Using low catalyst loadings (<1 mole percent), benzene and other functionalized arenes were selectively transformed to 1,4-cyclohexadienes in moderate to good yields in a completely metal-free reaction. Mechanistic studies support that this unprecedented visible light induced reactivity is enabled by the ability of the organic photoredox catalyst to harness the energy from two visible light photons to affect a single, high energy chemical transformation.

中文翻译:


可见光驱动的有机催化桦木还原



Birch 还原是一种强大的合成方法,它使用溶剂化电子将惰性芳烃转化为 1,4-环己二烯有价值的中间体,以构建分子复杂性。桦木还原传统上采用溶解在氨中的碱金属来产生溶剂化电子,用于还原未活化的芳烃,例如苯(Ered < -3.42 V vs. SCE)。光氧化还原催化剂在高还原性应用中越来越受欢迎,但没有报道表明其还原潜力足以还原苯。在这里,我们引入苯并苝酰亚胺作为新型有机光氧化还原催化剂,用于在环境温度下进行并由市售 LED 的可见光驱动的 Birch 还原。使用低催化剂负载量(<1 摩尔百分比),苯和其他官能化芳烃在完全不含金属的反应中以中等至良好的产率选择性转化为 1,4-环己二烯。机理研究表明,这种前所未有的可见光诱导反应性是通过有机光氧化还原催化剂利用两个可见光光子的能量来影响单个高能化学转化的能力实现的。
更新日期:2020-07-14
down
wechat
bug