Some common heterocyclic compound, 7411-23-6, name is 3,5-Dibromo-1H-1,2,4-triazole, molecular formula is C2HBr2N3, 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. Formula: C2HBr2N3
A solution of 1.4 g (36 mmol) of sodium hydroxide in13 mL of water was added to a solution of 8.0 g (36 mmol) of 3,5-dibromo-1H-1,2,4-triazole (1) in100 mL of acetone. The two-phase system thus formed was stirred at 20 C until it became homogeneous, and 4.6 g (36 mmol) of dimethyl sulfate was added dropwise at such a rate that the temperature of the mixture did not exceed 40 C. The mixture was then refluxed for 2 h. The reaction was assumed to be complete when the mixture became weakly acidic and sodium methyl sulfate precipitated. The mixture was filtered,and the solvent was distilled off from the filtrate under reduced pressure. The residue was washed with water, and the precipitate was filtered off and recrystallized from hexane. Yield 7.8 g (88 %), mp 64-65 C [22]. IR spectrum, nu, cm-1: 2951, 1717, 1699, 1464, 1418,1391, 1354, 1275, 1250, 1115, 1016, 989, 712, 700. 1H NMR spectrum, delta, ppm: 3.87 s (3H, CH3). 13C NMR spectrum, deltaC, ppm: 37.4 (CH3), 131.3 (C3),139.1 (C5). Mass spectrum, m/z (Irel, %): 243 (51.1) [M]+, 241 (100) [M]+, 239 (48.9) [M]+, 229 (21.3), 227 (48.3), 225 (24.2), 218 (1.2), 200 (6.1), 198 (12.3), 196 (5.1), 162 (14.5), 160 (13.1), 136 (33.4), 134 (34.9), 122 (30.6), 120 (31.3), 119 (6.3), 117 (7.4), 108 (14.6), 107 (7.7), 106 (16.2), 105 (8.9), 93 (15.9), 91 (18.9), 81 (40.9), 79 (32.5), 52 (12.7), 43 (33.8), 41 (12.2), 40 (13.3), 39 (9.1), 38 (18.5), 29 (53.2), 28 (10.7), 27(16.3), 26 (8.2), 15 (60.3), 12 (7.4).
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 7411-23-6, its application will become more common.
Reference:
Article; Tolstyakov; Russian Journal of Organic Chemistry; vol. 54; 10; (2018); p. 1537 – 1547; Zh. Org. Khim.; vol. 54; 10; (2018); p. 1525 – 1534,10;,
1,2,3-Triazole – Wikipedia,
Triazoles – an overview | ScienceDirect Topics