Lewis Acid Catalyzed Condensation-Cyclization Cascade: Direct Synthesis of Di/Trifluoromethyl-1,2,3,4-tetrahydroquinazolines

Direct Access to Acyl Fluorides from Carboxylic Acids Using a Phosphine/Fluoride Deoxyfluorination Reagent System

A fast and simple method for deoxyfluorination of carboxylic acids is presented. The protocol employs commodity chemicals (PPh₃, NBS, fluoride), affording products in excellent yields under mild conditions. Acyloxyphosphonium ion, the key reaction intermediate, was identified by NMR spectroscopic methods. Brønsted acidic conditions are essential for efficient C-F bond formation. The protocol displays scalability, high functional group tolerance, chemoselectivity, and easy purification of products. Deoxyfluorination of active pharmaceutical ingredients was established.

C(sp2)-H Trifluoromethylation of enamides using TMSCF3: access to trifluoromethylated isoindolinones, isoquinolinones, 2-pyridinones and other heterocycles

A method for the direct C(sp2)-H trifluoromethylation of enamides, including biologically relevant isoindolinones, isoquinolinones and 2-pyridinones using TMSCF3 under oxidative conditions is presented. The protocol is convenient, operationally simple and exhibits high tolerance across a multitude of relevant handles and functional groups.

Benzodiazines: recent synthetic advances

This review provides a comprehensive overview of the recent developments in synthetic strategies for benzodiazines, important scaffolds in medicinal chemistry.