Synthesis of (methanediyldibenzene-4,1-diyl)dimethanol (diol M)

In total, 78 g (0.37 mol) of 1,1-methanediylbis[4-(chloromethyl)benzene] and 77 g (0.78 mol) of potassium acetate were weighed and added into a 1000 cm³ round-bottom flask. Boiling pebbles and 600 cm³ of pure acetic acid were added. The contents of the flask were boiled gently for 6 h. In order to avoid the sediment sticking to the flask, the whole construction was shaken. The solution was then decanted into a beaker and the KCl remained in the flask. An amount of 1 L of distilled water was added to the solution. An oil crystallized while stirring and was separated. The product was filtered off using a funnel and, after being transferred to a flask, 300 cm³ of 10% aqueous Na₂CO₃ solution was poured over it, and then it was filtered again in the funnel. The resulting product was transferred to a 1000 cm³ flask and treated with 5% aqueous KOH solution (100 cm³) and 650 cm³ of methanol. The flask was heated under reflux. The state of boiling was maintained for 3 h. Then, the alcohol was distilled off. The separated precipitate was filtered off using a funnel and then washed with distilled water until reaching neutral pH. The crude product was purified by crystallization from ethyl acetate (1 g per 7 cm³ of the solvent).