Some common heterocyclic compound, 39806-90-1, name is 4-Iodo-1-methyl-1H-pyrazole, molecular formula is C4H5IN2, 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. name: 4-Iodo-1-methyl-1H-pyrazole
To a solution of 4-iodo-1-methyl-pyrazole (2.68 g, 12.9 mmol) and tert- butyl piperazine-1 -carboxylate (2.00 g, 10.7 mmol) in /-PrOH (40 ml_), ethylene glycol (0.66 g, 10.7 mmol), Cul (0.41 g, 2.15 mmol) and K3P04 (9.12 g, 43.0 mmol) were added. The reaction mixture was heated in sealed tube at 100C for 20h. Progress of the reaction was monitored by TLC and LCMS. After completion, the reaction mixture was concentrated in vacuo. The residue was diluted with H2O (150 ml_) and extracted with EtOAc (3 * 100 ml_). The organic layer was separated, washed with brine (100 ml_), dried over anhydrous Na2SC>4 and concentrated in vacuo. The crude residue obtained was purified by column chromatography (silica, 100-200 mesh, 0 to 2% MeOH in DCM) to afford tert-butyl 4-(1-methylpyrazol-4- yl)piperazine-1-carboxylate (0.93 g, 33%) as off-white solid. MS (ESI) m/e [M+H]7Rt/%: 267.00/2.45/82.5%. 1H NMR (400 MHz, CDCI3) 51.49 (s, 9H) 2.84 – 2.92 (m, 4H) 3.53 – 3.60 (m, 4H) 3.84 (s, 3H) 6.95 (s, 1 H) 7.21 (s, 1 H)
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 39806-90-1, its application will become more common.
Reference:
Patent; UCB BIOPHARMA SPRL; HALL, Adrian; (62 pag.)WO2018/138086; (2018); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics