Synthesis, Characterization, and Rapid Cycloadditions of 5-Nitro-1,2,3-triazine

The synthesis, characterization, and a study of the cydoaddition reactions of 5-nitro-1,2,3-triazine (3) are reported. The electron-deficient nature of 3 permits rapid cycloaddition with a variety of electron-rich dienophiles, including amidines, enamines, enol ethers, ynamines, and ketene acetals in high to moderate yields. H-1 NMR studies of a representative cycloaddition reaction between 3 and an amidine revealed a remarkable reaction rate and efficiency (1 mM, <60 s, CD3CN, 23 degrees C, >95%).