Something interesting about 3,5-Dibromo-1H-1,2,4-triazole

I am very proud of our efforts over the past few months and hope to 3,5-Dibromo-1H-1,2,4-triazole help many people in the next few years.

Reference of 7411-23-6, New Advances in Chemical Research in 2021. Chemo-enzymatic cascade processes are invaluable due to their ability to rapidly construct high-value products from available feedstock chemicals in a one-pot relay manner. 7411-23-6, name is 3,5-Dibromo-1H-1,2,4-triazole, molecular formula is C2HBr2N3, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, below Introduce a new synthetic route.

Triazole 1, 85.0 g (0.38 mol), was dissolved in 500 mL of ethyl acetate, 2-3 drops of trifluoroacetic acid were added, the mixture was heated to 50 C, and 75.0 g (0.87 mol) of 3,4-dihydro-2H-pyran was added over a period of 2.5 h. The mixture was refluxed for 1 h with stirring and evaporated, and the residue was recrystallized from toluene. Yield 111.5 g (95 %), mp 116-117 C [15]. IR spectrum, nu,cm-1: 2951, 2901, 2869, 2361, 1448, 1418, 1364, 1310,1289, 1240, 1204, 1184, 1082, 1055, 1042, 1001, 982,939, 912, 880, 847, 820, 793, 700, 563. 1H NMR spectrum,delta, ppm: 1.43-1.60 m (2H), 1.61-1.79 m (1H),1.84-2.04 m (2H), 2.04-2.20 m (1H), 3.54-3.76 m(1H), 3.91 d.d (1H, 3J = 3.2, 2J = 8.7 Hz), 5.54 d.d (1H, 3J = 2.5, 9.2 Hz). 13C NMR spectrum, deltaC, ppm: 21.7(CH2), 24.7 (CH2), 28.7 (CH2), 67.3 (CH2O), 84.6(OCH), 132.0 (C3), 140.0 (C5). Mass spectrum, m/z(Irel, %): 86 (5.8), 85 (100), 67 (10.8), 57 (11.1), 55 (8.4), 43 (8.9), 41 (18.9), 39 (6.5), 29 (17.8), 27 (8.7).

I am very proud of our efforts over the past few months and hope to 3,5-Dibromo-1H-1,2,4-triazole help many people in the next few years.

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