Yield: 96%

Reaction Conditions:

with phosphorus tribromide in dichloromethane at 0 - 20;

Steps:

8 Embodiment 8:1-bromo methyl propyl acetic acid methyl ester preparation
The 72g (0.5mol) 1-hydroxy methyl propyl b the nitrile dissolves in 500 ml methylene chloride, cooled to 0 °C -10 °C, and then the mixed solution is dropwise containing 46g (0.17mol) methylene dichloride solution of phosphorus tribromide, to maintain the temperature of the solution to 0 °C -10 °C, after dropping to room temperature to continue stirring reaction 1.5-5 hours, after the reaction, cooling the solution to 0 °C -10 °C, dropwise 20% sodium carbonate solution to adjust the pH value of 7.5-8.5, layered, collecting methylene chloride level, water layer extracted two times with methylene chloride, combined, concentrated to obtain red liquid 99.2g, yield 96.0%.

References:

Lunan Beite Pharmaceutical Co., Ltd;Zhang, Guimin;Wang, Zengxue;Ma, Qingwen CN105541786, 2016, A Location in patent:Paragraph 0051; 0052