The catalytic activity of iodine monobromide and iodine monochloride were investigated in the reaction, Et3SiOBun + BusOH ⇌ Et3SiOBus + BunOH. Pseudo first‐order rate constants were measured by gas chromatography, at 10°, 20°, 30°, and 40°C for iodine monobromide and at 10°, 20°, and 30°C for iodine monochloride, on reaction mixtures containing both butanols in excess.
The catalytic coefficients of both catalysts were evaluated from the observed rate constants as follows:
The activation paramaters were estimated from these data, and were compared with the values for iodine catalysis. These results are consistent with the mechanism previously proposed.