2,4-Di-tert-butylphenol → 3-(4-Hydroxy-3,5-dimethylphenyl)-5,7-bis(2-methyl-2-propanyl)-1-benzofuran-2(3H)-one

Participants

Reaction Conditions

Reaction Steps

1.5 ml (23 mmol) of methanesulfonic acid are added to a mixture of 154.8 g (0.75 mol) of 2,4-di-tert-butylphenol and 98.1 g (0.50 mol) of 3,5-dimethyl-4-hydroxymandelic acid in 500 ml of acetic acid which is stirred at 95° C. under nitrogen. After about 4 minutes, crystallisation of the product in the form of fine, white crystals begins. The reaction mixture is refluxed for another hour, then cooled to about 15° C., and the precipitated product is filtered off. The residue is washed with 250 ml of acetic acid and with 1500 ml of water. Drying gives 161.5 g (88%) of 3-(3,5-dimethyl-4-hydroxyphenyl)-5,7-di-tert-butylbenzofuran-2-one, melting point 225°-228° C. (compound (107), Table 1).

Provenance & Evidence