1-allyl-4-bromo-1H-pyrazole synthesis

Yield:13369-72-7 88%

Reaction Conditions:

with tetrabutylammomium bromide;sodium hydroxide in water;dimethyl sulfoxide at 20;

Steps:

9 Synthesis of 4-bromo-1-allyl-1H-pyrazole

4-bromopyrazole (14.7 g, 0.1 mol) at room temperature,3-bromopropene (12.1 g, 0.1 mol), tetrabutylammonium bromide (0.97 g, 0.003 mol),Dissolved in 6 ml of dimethyl sulfoxide (DMSO), adding sodium hydroxide solution [sodium hydroxide solution: 8.8 g (0.22 mol)The solution obtained by dissolving sodium hydroxide in 8 ml of water], the reaction is exothermic.After the dropwise addition is completed, the mixture is stirred at room temperature overnight, and diluted with water to quench.Extracted with dichloromethane, dried, concentrated and distilled under reduced pressure.The product was obtained in an amount of 16.5 g, and the yield was 88%.

References:

CN108863936,2018,A Location in patent:Paragraph 0035; 0036