Iodine-Promoted Formal [5+1] Annulation of 2-Vinylanilines and Thiurams: A Facile Approach to the Synthesis of 2-Aminoquinolines

Abstract

Quinolines especially 2-aminoquinolines are highly important heterocycles in medicinal chemistry. 2-Aminoquinolines can be synthesized via stepwise construction of quinoline ring followed by additional amination, however the protocol is cumbersome. Herein, we describe a [5+1] cyclization of 2-vinylanilines with tetraalkylthiuram disulfide in the presence of iodine and copper(II) triflate. This reaction directly employs readily available and low-cost thiuram as both C1 synthon and nitrogen source, providing a facile approach for one-step synthesis of a variety of 2-aminoquinolines in good to excellent yields.

Facile access to 3-sulfonylquinolines via Knoevenagel condensation/aza-Wittig reaction cascade involving ortho-azidobenzaldehydes and β-ketosulfonamides and sulfones

“…Moreover, numerous quinoline derivatives have been recently reported to possess intriguing pharmacological activities [3] including antiprotozoal [4][5][6][7], antitubercular [8,9], anticancer [10,11], anti-inflammatory [12], antioxidant [13], anti-HIV [14], antifungal [15], and an antineurodegenerative effect [16]. Hence, designing novel quinoline construction and functionalization techniques resulting in new or rare derivatives [17][18][19][20][21][22][23][24][25][26] is an important mission in the field of drug discovery and medicinal chemistry.…”