Synthesis of thieno[2,3-b]quinoline and selenopheno[2,3-b]quinoline derivatives via iodocyclization reaction and a DFT mechanistic study

In this letter, we report the regioselective iodocyclization reaction of 3-alkynyl-2-(methylthio)quinolines and 3-alkynyl-2-(methylseleno)quinolines for the synthesis of thieno[2,3-b]quinoline and selenopheno[2,3-b]quinoline derivatives. Furthermore, by employing various palladium-catalyzed Sonogashira, Suzuki, and Heck reactions, the structural diversification of the resulting halide derivatives, which can act as the important intermediates for building other valuable compounds, was achieved. All compounds were fully characterized by the FT-IR, mass, ¹H NMR, and ¹³C NMR spectral data. Finally, the structure of the thieno[2,3-b]quinoline derivative was confirmed by X-ray crystallography. This methodology provided a novel pathway to access quinoline fused heterocycles via iodocyclization reaction. Furthermore, the reaction process was well elucidated by density functional theory calculations.

Iodine mediated in situ generation of R-Se–I: application towards the construction of pyrano[4,3-b]quinoline heterocycles and fluorescence properties

Iodine mediated in situ generation of R-Se–I and its application towards the construction of pyrano[4,3-b]quinolin-1-one derivatives.

Regioselective and diastereoselective iodocyclization reaction of alkene-thioureas: an efficient approach to bicyclic β-lactams

Bicyclic β-lactams, i.e. 3-thia-1-dethiacephams were synthesized via a highly regioselective and diastereoselective iodocyclization reaction of alkene-thioureas with molecular iodine.