AB-INITIO STUDY OF THE 1,3-CYCLOADDITION OF METHYL AZIDE TO FLUORINATED ACETONITRILES

Transition state structures for polar 1,3-cycloaddition of methyl azid e to fluorinated acetonitriles have been optimized by ab initio molecu lar orbital calculations at the RHF/3-21G basis set level. The activat ion energies were also evaluated by single-point calculations at the R HF/6-31+G(double dagger) level on the RHF/3-21G geometries. Additional ly, the reactivity was rationalized in terms of the number of fluorine atoms in the molecules and the charge on the nitrile carbon. The regi oselectivity is correctly predicted by the activation energy differenc es, by the HOMO-LUMO interactions, and by the charge interactions.