Chemical Properties
LIGHT PINK-BEIGE TO BROWN CRYSTALS OR POWDER
Uses
It is used as a preservatives for coatings, slurries and to control microbial fouling in paper mills , oil field and leather process and water treatment process against microbial attack.
Preparation
4-Bromo-2,6-dimethylphenol is prepared by bromination of 2,6-dimethylphenol in glacial acetic acid at 15 ℃ and used as a microbicide in disinfectants.
General Description
Iodine initiated polymerization of 4-bromo-2,6-xylenol in tetrahydrofuran solution has been investigated. 4-Bromo-2,6-xylenol on bromination in chloroform or carbobn tetrachloride yields 3,4-dibromo-2,6-xylenol and 3,4,5-tribromo-2,6-xylenol.
Synthesis
In a 10 mL two-neck flask equipped with a reflux condenser, 2,6-dimethylphenol (0.25 mmol) and tetrabutylammonium bromide (161.2 mg, 0.50 mmol) were added. The flask was evacuated and backfilled three times with argon. To the reaction mixture was added ultrapure water (0.5 mL), trifluoroacetic acid (57.5 μL, 0.75 mmol) and 30% hydrogen peroxide (77 μL, 0.75 mmol). The reaction mixture was stirred at 25 °C under argon protection. Upon completion of the reaction, the reaction was quenched with 1:1 saturated aqueous sodium thiosulfate and saturated aqueous sodium bicarbonate and extracted with ether. The organic layers were combined, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. 1,3,5-Trimethoxybenzene or hexamethylbenzene was added as an internal standard and the NMR yield of the product was determined by 1H NMR analysis. The spectral data obtained for 4-bromo-2,6-dimethylphenol were consistent with those of commercially available standards.
Toxicity evaluation
LD50 (i.p., mouse) 650 mg/kg.
References
[1] Bulletin of the Chemical Society of Japan, 1989, vol. 62, # 10, p. 3373 - 3375
[2] Synthetic Communications, 2010, vol. 40, # 21, p. 3226 - 3232
[3] Organic Letters, 2006, vol. 8, # 19, p. 4291 - 4293
[4] Chinese Chemical Letters, 2012, vol. 23, # 4, p. 387 - 390
[5] Organic Letters, 2015, vol. 17, # 12, p. 2886 - 2889
