Electric Literature of 63680-90-0, In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 63680-90-0 as follows.
Step 2: Preparation of tert-butyl (3-chloro-1H-pyrazol-4-yl)carbamate Into a 2 L round bottom flask was added 3-chloro-1H-pyrazol-4-amine hydrochloride (100 g, 649 mmol) and THF (500 mL). To this mixture were added di-tert-butyldicarbonate (156 g, 714 mmol) followed by sodium bicarbonate (120 g, 1429 mmol) and water (50.0 ml). The mixture was stirred for 16 h, diluted with water (500 mL) and ethyl acetate (500 mL) and transferred to a separatory funnel. This gave three layers; bottom-a white gelatinous precipitate, middle-light yellow aqueous, top-auburn organic. The phases were separated collecting the white gelatinous precipitate and the aqueous layer together. The aqueous was extracted with ethyl acetate (2*200 mL) and the ethyl acetate extracts were combined, washed with brine (200 mL), dried over anhydrous sodium sulfate, filtered and rotary evaporated to give an auburn thick oil (160 g.). The thick oil was suspended in hexane (1000 mL) and stirred at 55 C. for 2 h. This gave a light brown suspension. The mixture was cooled to 0 C. and the solid collected by vacuum filtration and rinsed with hexane (2*10 mL). The sample was air dried to constant mass to afford (3-chloro-1H-pyrazol-4-yl)carbamate (102.97 g, 72% yield, 80% purity) as a light brown solid: mp 137-138 C.; 1H NMR (400 MHz, CDCl3) delta 10.69 (s, 1H), 7.91 (s, 1H), 1.52 (s, 9H).
According to the analysis of related databases, 63680-90-0, the application of this compound in the production field has become more and more popular.
Reference:
Patent; DOW AGROSCIENCES LLC; Buysse, Ann M.; Niyaz, Noormohamed M.; Demeter, David A.; Zhang, Yu; Walsh, Martin J.; Kubota, Asako; Hunter, Ricky; Trullinger, Tony K.; Lowe, Christian T.; Knueppel, Daniel; Patny, Akshay; Garizi, Negar; LePlae, JR., Paul Renee; Wessels, Frank; Ross, JR., Ronald; DeAmicis, Carl; Borromeo, Peter; US2013/288893; (2013); A1;,
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