We present a sustainable one-pot, copper-catalyzed synthesis of 2-phenyl-2H-chromenes with excellent regioselectivity, requiring only a 0.5 mol% catalyst.
The mechanism of the addition of 2-aryl-3-nitro-2H-chromenes to pyrazole was evaluated in the framework of molecular electron density theory based on the results of the wb97xd/6-311+G(d,p) (IEFPCM) calculations.
A Cu-catalyzed asymmetric methylboration of 1,2-dihydroquinolines, 2H-chromenes and 2H-thiochromenes providing boryl products bearing two adjacent chiral centers with excellent selectivities, up to 99 : 1 dr and 99.9% ee, has been realized for the first time.
This review summarizes modern stereoselective enolate and homoenolate Michael addition/annulation reactions to nitroalkene-containing benzo-fused heterocycles, enabling efficient access to complex polycyclic heterocycles with biological importances.
The present review covers all isocyanide-based multicomponent reactions for the preparation of benzopyrans, which serve as the parent cores of many essential drugs, natural compounds, and biological compositions.