REACTION BETWEEN Δ2-OXAZOLIN-5-ONES AND NITROSOBENZENE. FORMATION OF 1,2,4-OXADIAZOLINES

Article abstract of DOI:10.1016/S0040-4020(01)97624-0

2,4-diphenyl- and 2-p-methylphenyl-4-phenyl-Δ²-oxazolin-5-ones react at 80-110 deg C with nitrosobenzene to give benzamidines.However, reactions conducted at room temperature afford in high yield, the heretofore undescribed Δ⁴-oxadiazolin-3-carboxylic acids by regiospecific 1,3-dipolar cycloaddition.Thermal decomposition of the oxadiazolinecarboxylic acids gives the corresponding benzamidines.