Influence of the radical center on the basic hydrolysis reaction of 4-dihalomethyl-3-imidazoline-3-oxide

Conclusions

• 1. The nitroxyl group in 4-dihalomethyl-3-imidazoline-3-oxide-1-oxyls substantially modifies the reactivity of the dihalomethyl group, giving it greater activity in comparison with the diamagnetic analog in the basic hydrolysis reaction and greater inclination to oxidation by the radical center.

• 2. The main products of hydrolysis in aqueous alcohol of diamagnetic 4-dihalomethyl-3-imidazoline-3-oxide are 4-dialkoxymethyl derivatives, and of nitroxyl radicals with the 4-dihalodimethyl group, a mixture of paramagnetic and diamagnetic 4-carboxy-3-imidazoline-3-oxides.

• 3. In contrast to the diamagnetic, in the paramagnetic derivatives of 4-dihalodimethyl-3-imidazoline-3-oxides the reactivity changes in going from the dibromomethyl to the dichloromethyl derivative, i.e., the rate of basic hydrolysis increases.

• 4. Under the reaction conditions of basic hydrolysis the paramagnetic 4-dihalomethyl-3-imidazoline-3-oxides are oxidized by radicals of the 3-imidazoline-3-oxide, 2- and 3-imidazoline and imidazolidinone series; the radical centers of these are easily reduced to amino groups.