Some common heterocyclic compound, 930-36-9, name is 1-Methylpyrazole, molecular formula is C4H6N2, 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: C4H6N2
A mixture of phosphoryl chloride (467 gm, 3.045 moles) and DMF was stirred for 1 hour at 0-5 C. The reaction is exothermic so temperature should be below 5 C. To this slowly added 1-methyl-1H-pyrazole (50 gm, 0.6090 moles) and stirred for 30 min at 0-5 C. Then slowly raised the temperature from 20-30 C. to 60-70 C. and stirred for 10-15 hours. Progress of the reaction was monitored by HPLC. The reaction mixture was cooled to 0-5 C., to this added ethyl acetate (250 ml), DM water (1 L) and aqueous ammonia solution (350 ml, pH-6 to 7). The reaction mixture was stirred for 1 hour at 20-30 C. The inorganic salt obtained was filtered off, washed with ethyl acetate (250 ml). The filtrate was transferred in to a separating funnel. The reaction mixture was allowed to settle. The organic layer was separated and aqueous layer was extracted with ethyl acetate (250 ml). The entire organic layer was transferred to the reaction vessel, stirred for 10-15 min and separated the final aqueous layer and organic layer. The combined organic layer having 1-methyl-1H-pyrazole-4-carbaldehyde and ethyl acetate was used as such for Step 2 without any purification or isolation at this step.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 930-36-9, its application will become more common.