Name | 1,4-Dibromo-2,5-dimethoxybenzene |
Synonyms | 2,5-Dibromo-1,4-dimethoxybenzene 1,4-Dibromo-2,5-dimethoxybenzene 2,5-Dimethoxy-1,4-dibromobenzene Benzene,1,4-dibromo-2,5-dimethoxy- |
CAS | 2674-34-2 |
InChIKey | CHCLRVOURKGRSW-UHFFFAOYSA-N |
Molecular Formula | C8H8Br2O2 |
Molar Mass | 295.96 |
Density | 2,24 g/cm3 |
Melting Point | 145.0-149.0℃ |
Boling Point | 290.3±35.0 °C(Predicted) |
Water Solubility | Insoluble in water. |
Appearance | White solid |
BRN | 1953103 |
Storage Condition | Room Temprature |
Refractive Index | 1.4947 (estimate) |
MDL | MFCD00025694 |
Use | Brief Introduction 1, 4-dibromo-2, 5-dimethoxybenzene is an organic intermediate that can be used for the preparation of 1, 4-dibromohydroquinone, which can be prepared by the reaction of p-phenylene oxide dimethyl ether and elemental bromine. |
Hazard Symbols | Xi - Irritant |
Risk Codes | 36/37/38 - Irritating to eyes, respiratory system and skin. |
Safety Description | S37/39 - Wear suitable gloves and eye/face protection S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S36 - Wear suitable protective clothing. |
WGK Germany | 3 |
Hazard Note | Irritant |
Downstream Products | 2,5-dimethoxyterephthalohydrazide 4-Bromo-2,5-dimethoxybenzaldehyde |
Method 1:
Synthesis of 1, 4-dibromo-2, 5-dimethoxybenzene: 20.0g(0.145mol,1.0eq) of p-phenylene dimethylether was added into a ML reaction flask, and 55ml of glacial acetic acid was dissolved by ultrasound; A solution of 15ml of Br2(0.290mol,2.0eq) and 15ml of glacial acetic acid was added dropwise at room temperature. After 1.5 hours, the mixture was stirred at room temperature for 2.5 hours; after the upper layer of the refrigerator is cooled to below 10 ° C. (do not solidify acetic acid), Suction filtration is performed; And the filter cake is washed with petroleum ether to obtain a white solid, weighing 35.6g after vacuum drying, with a yield of 83.6%. 1H NMR(400MHz,CDCl3) delta;7.11(s,2H),3.85(s,6h).
Method 2:
Add 1.5ml of acetonitrile, 0.5mmol of 1, 4-dimethoxybenzene, 0.65mmol of liquid bromine (Br2) and 0.041mmol of nitrogen dioxide to a reaction tube of about 45ml, then add a magnet, close the reaction tube, the reaction tube was placed in a reaction tank at a temperature of 30 ° C. And stirred magnetically for 24 hours. After completion of the reaction, the reaction system was cooled to room temperature, and the internal standard 1,2,4, 5-tetramethylbenzene was added. Gas Chromatography Analysis gave an internal standard yield of 76% for the product. The above experimental procedure was repeated, but no internal standard substance was added, and the obtained product was separated and purified by column chromatography to obtain 1, 4-dibromo-2, 5-dimethoxybenzene product.