A Practical Synthesis of 1‐Azine‐pyridin‐2(1H)‐ones from Azine N‐oxides and Pyridin‐2(1H)‐ones under Mild Reaction Conditions

Abstract

Through direct coupling reaction of azine N‐oxides with readily available pyridin‐2(1H)‐ones, a facial and practical strategy was developed for the synthesis of 1‐azine‐pyridin‐2(1H)‐one derivatives in the presence of diethyl H‐phosphonate, CCl4 and Et3N at room temperature for 0.5 h. This reaction features metal‐free and mild reaction conditions, short reaction time, ease of scale up and wide scope of products.

Recent Advances in the Transition-Metal-Free Arylation of Hetero­arenes

“…The reaction takes place at room temperature in a short time and uses diethyl H-phosphonate, carbon tetrachloride, and triethylamine reagents, and acetonitrile as the solvent (Scheme 50). 59 Reactive diethyl chlorophosphate is formed in situ in the reaction and enables the C2 carbon of the quinoline N-oxide to gain an electrophilic character. The starting compounds required for this environmentally friendly methodology are relatively inexpensive and easily available.…”