Chemical Properties
white crystalline powder
Uses
1,4-Dibromo-2,5-dimethoxybenzene was used in the preparation of poly[(9,9-bis(6-(dibromohexyl)-2,7-fluorene))-
alt-1,4-(2,5-dimethoxybenzene)], a water-soluble polyfluorene derivative.
Synthesis Reference(s)
The Journal of Organic Chemistry, 63, p. 3764, 1998
DOI: 10.1021/jo9721812
General Description
Crystal structure of 1,4-dibromo-2,5-dimethoxybenzene has been reported to be monoclinic and its asymmetric unit is composed of one-half of the molecule. Lithium diisopropylamide (LDA) mediated metallation of 1,4-dibromo-2,5-dimethoxybenzene has been proposed.
Synthesis
Example 2: Preparation of 2,5-dibromo-1,4-dimethoxybenzene (2); In a 1 liter round-bottomed flask, a solution of chloroform (50 mL) of bromine (35.2 g, 220 mmol) was added slowly and dropwise to a solution of chloroform (400 mL) of 1,4-dimethoxybenzene (13.8 g, 100 mmol). The reaction mixture was stirred at room temperature for 3 hours before 100 mL of saturated Na2CO3 solution was added to quench the reaction. The organic layer was separated, washed sequentially with water and saturated brine, and dried over anhydrous sodium sulfate. The solvent was removed by concentration under reduced pressure and the resulting residue was recrystallized from ethanol to give pure 2,5-dibromo-1,4-dimethoxybenzene (25.8 g, 85% yield). The product was characterized by 1H NMR (CDCl3): δ 7.128 (s, 2H), 3.873 (s, 6H).
References
[1] Tetrahedron, 1999, vol. 55, # 36, p. 11127 - 11142
[2] Tetrahedron Letters, 1998, vol. 39, # 35, p. 6349 - 6350
[3] Organic Process Research and Development, 2016, vol. 20, # 2, p. 284 - 296
[4] Journal of the American Chemical Society, 2003, vol. 125, # 37, p. 11241 - 11248
[5] Journal of Materials Chemistry A, 2017, vol. 5, # 44, p. 22933 - 22938
