Electric Literature of 67-51-6, These common heterocyclic compound, 67-51-6, name is 3,5-Dimethyl-1H-pyrazole, 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.
In a 250 ml reaction vessel, 3,5-dimethyl-1 H-pyrazole x51 (0.5 g, 5 mmol), I2 (0.79 g, 30 mmol) and CAN (1.71 g, 3 mmol) are dissolved in 70 ml of CH3CN and stirred at room temperature for 16 h. The solvent is evaporated, the residue dissolved in AcOEt and washed with a 10 % aqueous solution of Na2S2U3 and brine. The aqueous phase is re- extracted with AcOEt and the combined organic phases are dried over Na2SO4, filtered and concentrated to dryness to afford 1.15 g (100 %) of crude 4-iodo-3,5-dimethyl-1 H- pyrazole x52, which is used in the next step without further purification.LC-MS (MH+): 223.
Statistics shows that 3,5-Dimethyl-1H-pyrazole is playing an increasingly important role. we look forward to future research findings about 67-51-6.
Reference:
Patent; UCB S.A.; WO2006/128692; (2006); A2;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics