4-Chlorobenzenes~~ lfonyl isocyanate (I) and 4-toluenesulfonyl isocyanate (11) reacted with 2, 6-disubstituted and 2, 4, 6-trisubstituted phenols. Kinetic studies showed the reactions to be second order, first order in isocyanate and first order in phenol. The relative rates of reaction of the phenols were 2, 6-diisopropyl-> 2, 6-dimethyl-> 2, 6-dibromo-> 2, 4, 6- tri-tert-butyl-> 2, 6-di-tert-butyl-> 2, 4, 6-tribromo-. Isocyanate I was found to be somewhat ...