[He, Wei-Min] Hunan Univ Sci & Engn, Hunan Prov Engn Res Ctr Ginkgo Biloba, Yongzhou 425100, Peoples R China.
A general, effective and convenient protocol for the direct synthesis of various 2-aminoquinolines (39 examples) through AgBF4-catalyzed amination of quinoline N-oxides with isothiocyanates under base-, oxidant-free and mild conditions was developed. The transformation could be performed on a gramscale and in a sequential manner starting from quinoline N-oxide to the synthesis of benzo[4,5] imidazo [1,2-a] quinoline.
Deep eutectic solvent;Multicomponent reaction;Selenocyanation;Alkynes;H-bonding
By employing cheap and biodegradable natural deep eutectic solvent as the catalyst and reaction media, the selective selenocyanation of activated alkynes via an intermolecular H-bonding activation pathway has been achieved, which allows for the efficient construction of various Z-vinyl selenolates.
A practical and eco-friendly method for the clean preparation of a variety of Z-beta-thiocyanate alkenyl esters via lactic acid-catalyzed multicomponent hydrothiocyanation reaction was established. In the subgram-scale synthesis, Z-beta-thiocyanate alkenyl esters were exclusively generated, and the product could be easily isolated in high purity via extraction. In the large-scale synthesis, the pure products could be simply collected through liquid-liquid separation. The eco-friendly lactic acid played a dual function in the transformation, serving as recyclable biomass catalyst and recyclable reaction medium.