Catalyst-Free Oxytrifluoromethylation of Alkenes through Paired Electrolysis in Organic-Aqueous Media
作者:Wolfgang Jud、C. Oliver Kappe、David Cantillo
DOI:10.1002/chem.201804708
日期:2018.11.22
A mild, catalyst‐free electrochemical oxytrifluoromethylation of alkenes has been developed. The procedure is based on the paired electrolysis of sodium triflinate and water in an undivided cell. Anodic oxidation of the triflinate anion generates trifluoromethyl radicals that react with the alkene. Water plays a dual role as oxidant for the cathode and nucleophile. The method has been utilized to prepare
Sunlight-driven trifluoromethylation of olefinic substrates by photoredox catalysis: A green organic process
作者:Munetaka Akita、Takashi Koike
DOI:10.1016/j.crci.2015.01.013
日期:2015.7
types of catalytic photoredox processes following the reductive quenching cycle (RQC) and the oxidative quenching cycle (OQC), the discussion is focused on organic transformations based on OQC, in particular the trifluoromethylation of olefinic substrates with electrophilic trifluoromethylating reagents furnishing solvolytic addition products and substitution products. It is concluded that catalytic
Cobalt–Tertiary-Amine-Mediated Hydroxytrifluoromethylation of Alkenes with CF<sub>3</sub>Br and Atmospheric Oxygen
作者:Qiankun Li、Wu Fan、Deqian Peng、Bingyin Meng、Shaohan Wang、Rui Huang、Shihao Liu、Suhua Li
DOI:10.1021/acscatal.0c00498
日期:2020.4.3
The mild and efficient hydroxytrifluoromethylation of alkenes with bromotrifluoromethane (CF3Br) and atmospheric oxygen mediated by cobalt-tertiary amine is described. This reaction proceeds with broad substrate scope and good functional group compatibility. Mechanistic studies indicate that the reaction proceeds through a radical pathway, which is enabled by combination of the previously unexplored
Three-component Oxytrifluoromethylation of Alkenes: Highly Efficient and Regioselective Difunctionalization of CC Bonds Mediated by Photoredox Catalysts
作者:Yusuke Yasu、Takashi Koike、Munetaka Akita
DOI:10.1002/anie.201205071
日期:2012.9.17
Here comes the sun: A facile vicinal difunctionalization of alkenes, oxytrifluoromethylation, was established by visible‐light‐driven photoredox catalysis. Judicious choice of the CF3 source is key. Nucleophiles such as water, alcohols, and carboxylic acids can be used in this highlyefficient (2–4 h) and regioselective (100 %) transformation using light‐emitting diode (LED) lamps and natural sunlight
yields under extremely mild conditions without catalysts. We found that our reaction can be applied to not only styrenes but also various aliphatic alkenes with excellent selectivity; no ketone was detected in most of our cases. Another feature of our discovery is “simple”. The reaction was carried out in air, irradiated by visible light, at room temperature and most importantly no catalyst was needed
含CF 3的分子在制药,农用化学品和材料中的重要性引起了人们对这些化合物的合成方法的浓厚兴趣。为了丰富三氟甲基化方法学,我们仔细检查了使用碘代三氟甲烷进行烯烃的羟基三氟甲基化的底物范围,该反应在没有催化剂的情况下,在极温和的条件下以良好的收率提供了β-三氟甲基醇。我们发现,我们的反应不仅可以应用于苯乙烯,而且还可以以优异的选择性应用于各种脂肪族烯烃。在我们大多数情况下,未检测到酮。我们发现的另一个特征是“简单”。该反应在室温下在可见光辐射的空气中进行,最重要的是不需要催化剂。CF的解决方案DMSO中的3 I用作简便的三氟甲基化试剂,简化了气态CF 3 I的利用。基于19 F NMR光谱,我们在该反应中观察到CF 3 I与叔胺之间的卤素键。相互作用可以通过可见光照射促进单电子转移。