Category: 1646-54-4

Electric Literature of 1646-54-4, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 1646-54-4 name is 1,4-Dibromo-2,3,5,6-tetramethylbenzene, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

To a 3L four necked round bottom flask fitted with refluxedcondenser and mechanical stirrer, were added 1,4-dibromotetramethylbenzene (30 g, 102.73 mmol), pridine(1250 ml) and water (180 ml). The reaction mixture was heated at100 C with constant stirring. To this reaction mixture, KMnO4(82.5 g, 522.15 mmol) was added in small aliquots in 45 min. Aftercomplete addition the reaction mixture was refluxed for next 5 h.The hot solution was filtered to remove MnO2 from reactionmixture and the solvent concentration of at vacuo. To the residualsolid were added water (1500 ml) and NaOH (70 g). The reactionmixture was stirred and heated at 100 C. KMnO4 (82.5 g,522.15 mmol) was added in small aliquots in 1 h. The reactionmixture was refluxed for next 5 h. Excess of KMnO4 was destroyedby caution addition of ethanol (60 ml). The hot solutionwas filteredto separate MnO2. The filtrate was acidified with aqueous HCl (5N).After solvent was removed under reduced pressure, colorlesscompound obtained. Acetonewas added to this solution and stirredfor 40 min. It was filtered to remove NaCl and filtrate wasconcentrated under reduced pressure to obtain 20 g (47%) product.The colorless powder from acetone .13C NMR (Acetone-d6, 75 MHz)deltad 116.41m (CBr), 138.39 (C-COOH), 165.87 (C]O).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 1,4-Dibromo-2,3,5,6-tetramethylbenzene, and friends who are interested can also refer to it.

Reference:
Article; Bandyopadhyay, Arkasish; Halim, Md. Ershad; Hossain, Md. Elius; Shinmyozu, Teruo; Journal of Molecular Structure; vol. 1213; (2020);,
Bromide – Wikipedia,
bromide – Wiktionary

A common heterocyclic compound, 1646-54-4, name is 1,4-Dibromo-2,3,5,6-tetramethylbenzene, molecular formula is C10H12Br2, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. 1646-54-4.

The reaction pathway is shown in Scheme 1. H4dbtec ligand was prepared according literature [13] and with a little modification. To a four-necked flask equipped with a reflux condenser and a mechanical stirrer, 3,6-bromo-tetramethylbenzene (0.171 mol), 2.1 L pyridine and 280 mL water were added. The reaction mixture was heated to 100 C while stirring. KMnO4 (0.859 mol) was added in small portions and the mixture was refluxed for 5 h. The warm solution was separated from MnO2 by filtration and the solvent evaporated under reduced pressure. 280 mL water and 112 g NaOH were added to the residual solid. After the combined mixture was heated up to 100 C, KMnO4 (0.859 mol) was added again in small portions and the mixture was refluxed for 5 h. The excess KMnO4 was destroyed by the cautious addition of 140 mL ethanol. The MnO2 was removed from the hot mixture by filtration. The filtrate was acidified with aqueous HCl (5 M, 600 mL). After the solvent was revaporated, the residue was washed with acetone. The resultant solid was dried. The yield was 46 g (66%). 1H NMR (300 MHz; DMSO-d6) no signals. 13C NMR (100 MHz; DMSO-d6) deltac 115.51, 137.57, 166.27.

The synthetic route of 1,4-Dibromo-2,3,5,6-tetramethylbenzene has been constantly updated, and we look forward to future research findings.

Reference:
Article; Zhang, Liang-Liang; Guo, Yu; Wei, Yan-Hui; Guo, Jie; Wang, Xing-Po; Sun, Dao-Feng; Journal of Molecular Structure; vol. 1038; (2013); p. 73 – 77;,
Bromide – Wikipedia,
bromide – Wiktionary