CONTROL OF THE ROTATIONAL BARRIER AND SPATIAL DISPOSITION OF THE N-(2'-METHYLPHENYL) GROUP IN SUCCINIMIDES BY SUBSTITUENT AND SOLVENT EFFECTS

Both the rotational barrier for the N-(2'-methylphenyl) group in benzy lamino-N-(2'- methylphenyl)succinimides 1a-h (X = NEt2 OMe, Me, H, F, Cl, CO2Me and NO2) and the spatial disposition of the N-(2'-methylphen yl) group in N-(4'-substituted dihydro-9,10-ethanoanthracene-11,12-dic arboximides 2a-h (X = NEt2, OMe, Me, H, F, Cl, CO2Me and NO2) are cont rolled by the substituents present mid the solvents used. The rotation al barrier of 1 decreases with an increase in sigma(p) (Hammett's para substituent constant of X) and increases in proportion to an increase of the solvent parameter [E-T(30)]. Clear correlation was observed in the plots of the synlanti ratio of 2 against sigma(m) (Hammett's meta -substituent constant of X) and the ratios are also controllable by th e solvent polarity (mu).