Laboratorio de Compuestos Organometálicos y Catálisis (Unidad Asociada al CSIC), Departamento de Química Orgánica e Inorgánica (IUQOEM), Facultad de Química, Universidad de Oviedo, 33071, Oviedo, Spain.
WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK.
Angew Chem Int Ed Engl. 2016 Dec 23;55(52):16145-16148. doi: 10.1002/anie.201609929. Epub 2016 Nov 28.
Shattering the long-held dogma that organolithium chemistry needs to be performed under inert atmospheres in toxic organic solvents, chemoselective addition of organolithium reagents to non-activated imines and quinolines has been accomplished in green, biorenewable deep eutectic solvents (DESs) at room temperature and in the presence of air, establishing a novel and sustainable access to amines. Improving on existing methods, this approach proceeds in the absence of additives; occurs without competitive enolization, reduction or coupling processes; and reactions were completed in seconds. Comparing RLi reactivities in DESs with those observed in pure glycerol or THF suggests a kinetic anionic activation of the alkylating reagents occurs, favoring nucleophilic addition over competitive hydrolysis.
打破了有机锂化学需要在惰性气氛中、有毒有机溶剂中进行的长期教条,在绿色可再生深共熔溶剂(DESs)中,在室温下、空气中、无需添加试剂的条件下,实现了对非活化亚胺和喹啉的选择性有机锂试剂加成,为胺类化合物的合成提供了新的、可持续的方法。与现有的方法相比,这种方法不需要添加剂;不会发生竞争性烯醇化、还原或偶联反应;反应在几秒钟内完成。在 DESs 中与在纯甘油或 THF 中观察到的 RLi 反应性进行比较,表明烷基化试剂发生了动力学阴离子活化,有利于亲核加成而不是竞争性水解。