Diastereoselective synthesis of CF₃-oxazinoquinolines in water

A highly efficient stereoselective synthesis of CF3-oxazinoquinolines was elaborated using the reaction of CF3-ynones with quinolines in water. It was demonstrated that under these green conditions, the reaction proceeds up to 20 times faster to provide target compounds in almost quantitative yields. Moreover, this method is devoid of any chromatographic purification to give CF3-oxazinoquinolines with complete diastereoselectivity. The presented eco-friendly approach was found much more efficient than standard reactions in organic solvents. The synthetic utility of the prepared CF3-oxazinoquinolines was demonstrated.