Abstract
Conditions for obtaining p-thiocresol by the catalytic reduction of p-toluenesulfonyl chloride with molybdenum sulfide catalyst and with pressure have been investigated.
Catalytic reduction by use of cyclohexane as a solvent with an initial pressure at 100 atmospheres showed the reaction at around 100°C and yielded di-p-tolyl disulfide as a main product and a small amount of p-thiocresol. However, the reaction was accompanied with hydrolysis of sample to give p-toluenesulfonic acid as a by-product and the yield of reduction product was below 50% for this reason.
In order to prevent this hydrolysis, the reaction was proceeded with an addition of alumina (Al2O3), magnesium oxide (MgO) or calcium oxide (CaO) and these were found to be fairly effective. This enabled to give an increase in yield of reduction product, gave p-thiocresol as a main product at 160-200°C. The yield of p-thiocresol was 79% with the addition of CaO and the effects of these additives were in order of CaO > MgO > Al2O3.
