The Reaction of N-Methyl-1,2,4-triazoline-3,5-dione with Tetracyclopropylethylene. Formation of an Unusual Meso-ionic Product and Its Rearrangement to the Diazetidine

The reaction of N-methyl-1,2,4-triazoline-3,5-dione and tetracyclopropylethylene results in the quantitative formation of a meso-ionic compound. The formation of this unusual compound is likely the result of the unique conformational and steric properties of the cyclopropyl groups which inhibit the expected reaction pathways. The meso-ionic compound undergoes an unprecedented rearrangement to the diazetidine upon warming to 55 °C.