Theoretical study of the mechanism of the addition of diazomethane to ethylene and formaldehyde. Comparison of conventional ab initio and density functional methods

The 1,3-dipolar cyclization reactions of diazomethane with ethylene and formaldehyde, including the nitrogen elimination reactions from the cycloadducts, were investigated through density functional and conventional ab initio techniques. Results showed that the exothermicity of the reactions is underestimated by density functional methods with respect to CCSD(T) because of an overestimation of the C-N dissociation energy of diazomethane.