Synthesis
General procedure: 2,5-dimethylhexane-2,5-diol (10.0 g, 68.4 mmol) was placed in 50 mL of concentrated hydrochloric acid and stirred. The reaction mixture was kept at room temperature for 16 hours. Upon completion of the reaction, it was diluted with 50 mL of water and extracted with ether (3 x 50 mL). The organic phases were combined and concentrated to about 30 mL. the precipitated white crystalline solid was collected by filtration (8.8 g, 70% yield) without further purification.1H NMR (400 MHz, CDCl3) data were as follows: δ = 1.96 (s, 4H), 1.61 (s, 12H), in agreement with the literature.
2,5-Dichloro-2,5-dimethylhexane (5.50 g, 30.0 mmol) and 2-bromotoluene (10.3 g, 60.0 mmol) were dissolved in 60 mL of dichloromethane. Aluminum trichloride (400 mg, 3.00 mmol) was added slowly over 5 min. The reaction was stirred under argon protection for 1 hour. After completion of the reaction, 50 mL of water was added to separate the organic and aqueous layers. The aqueous layer was extracted with hexane (3 x 50 mL). The organic phases were combined, dried with anhydrous magnesium sulfate, filtered and concentrated under reduced pressure to give an oily product. The oily product was dissolved in 75 mL of boiling methanol and subsequently cooled in an ice bath. After filtration, white crystals (6.6 g, 78% yield) were obtained.1H NMR (400 MHz, CDCl3) data were as follows: δ = 7.43 (s, 1H), 7.15 (s, 1H), 2.35 (s, 3H), 1.66 (s, 4H), 1.26 (s, 12H), which is in accordance with the report in the literature [5].
References
[1] Tetrahedron Letters, 1997, vol. 38, # 46, p. 8067 - 8070
[2] Chemistry - A European Journal, 2013, vol. 19, # 10, p. 3504 - 3511
[3] Tetrahedron Letters, 2017, vol. 58, # 50, p. 4703 - 4708
[4] Patent: KR101515814, 2015, B1. Location in patent: Paragraph 0307; 0308
