Phenol → 4-Hydroxythiobenzamide

Participants

Reaction Steps

At a temperature and in the manner as described in Example 1, 69 g of potassium thiocyanate (0.7 mol) and 52 g of phenol (0.55 mol) are stirred with 0.5 l of 98% hydrofluoric acid, and subsequently, the mixture is stirred for 3 days at room temperature. 0.3 l of hydrofluoric acid are then distilled off at normal pressure and a bath temperature of up to 60° C, the remainder is cooled and the residue is stirred with ice and water. The crude product precipitated is suction-filtered and may be purified by dissolving in dilute soda solution at room temperature, clarifying the solution and subsequent precipitation of the product with mineral acid or by recrystallization from water. The 4-hydroxy-thiobenzamide so obtained has a melting point of 192° - 193° C. The yield is 85% of the theoretical yield, relative to the phenol used.

Provenance & Evidence