Hydrochlorination and hydrobromination of N-(N-arylsulfonylbenzimidoyl)-1,4-benzoquinonimines

Article abstract of DOI:10.1023/A:1012377401470

The direction of hydrohalogenation of N-substituted p-quinonimines was predicted on the basis of orbital coefficients of the C² and C³ atoms in the lowest unoccupied molecular orbital, calculated by the PM3 method. It was assumed that the reaction is orbital-controlled and that the initial act of hydrohalogenation is nucleophilic attack by halide ion. The proposed approach was verified by experimental hydrochlorination and hydrobromination of N-(N-arylsulfonylbenzimidoyl)-1,4-benzoquinonimines which take up HHlg molecule following the 1,4-addition scheme, i.e., the halogen atom adds to C² of the quinoid ring.