Base-controlled chemoselectivity reaction of vinylanilines with isothiocyanates for synthesis of quinolino-2-thione and 2-aminoquinoline derivatives.

Here, we report a base-controlled chemo-selective reaction of vinylanilines with alkyl/aryl isothiocyanates to afford quinolino-2-thione and 2-aminoquinoline derivatives. The quinolino-2-thiones could be obtained in high yields in the presence of Et3N. Particularly interesting is that the reaction could produce the 2-aminoquinolines in the presence of K3PO4 with high selectivity.

Base-catalyzed thio-lactamization of 2-(1-arylvinyl)anilines with CS2 for the synthesis of quinoline-2-thiones.

Here we show that the base-catalyzed thio-lactamization of 2-(1-arylvinyl)anilines with CS2 is a powerful methodology to synthesize quinoline-2-thiones. This thio-lactamization uses inexpensive and versatile 2-(1-arylvinyl)anilines, which are easily available from the reaction of amines and alkynes. Compared to the known strategy in the literature, this method features the advantages like a short synthesis step and easily available starting materials.

Synthesis of beta-aminoketones and construction of highly substituted 4-piperidones by mannich reaction induced by persistent radical cation salts.

A Mannich reaction of imines and ketones induced by persistent radical cation salts was investigated, and a series of Mannich bases, beta-aminoketones, were synthesized. A novel cyclization to form the 4-piperidone skeleton was achieved in a tandem process. The reaction can be rationalized as a radical cation process supported by various evidence.