Synthesis of Ethyl 3,5-bis bromomethyl 4- hydroxybenzoate

The compound was prepared by a previously published procedure [21]. 2,6-bis(hydroxymethyl)-4-hydroxybenzoate (0.58 g, 16 mmol) was added whilst stirring to a solution of hydrogen bromide in acetic acid (30 % HBr, 2 mL, 50 mmol). After 5 min a clear solution formed, from which after 10 min an orange precipitate separated. The sticky mass was cooled, filtered and washed thoroughly with cold petroleum ether until an orange solid was obtained. The resulting solid was dried in vacuo. (0.83 g, 90.45 %). 

The compound was prepared after a previously published procedure [50]. 2.6-bis(hydroxymethyl)-4-methylphenol (16 g, 0.12 mol) was stirred with activated Mn02 (85 %, 80 g, 1.14 mol) in chloroform (250 mL) at room temperature for 16 h. The black slurry was then filtered through Celite and the yellow filtrate was concentrated to a brown oil in vacuo. The residue was taken up in hot toluene (40 mL) and filtered. A brown oil was obtained after removal of the solvent in vacuo which solidified upon standing. The solid was dissolved in ethanol (30 mL) and added dropwise to cone, hydrochloric acid (80 niL) at 40 °C. The mixture was subsequently stirred for 2 h at room temperature and the white powder obtained was filtered off and washed with water until the filtrate was pH neutral (3.94 g, 17.91 %). 

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