Yield:163704-71-0 79%

Reaction Conditions:

with pyridine for 4 h;Reflux;

Steps:

1 This embodiment provides a preparation method of compound 3 (ie step S1):

Compound 1 (2,6-isopropylaniline, 0.2mol, 35.4g)Dissolved in 75ml Pyridine,Then add compound 2 (4-toluenesulfonyl chloride, 0.22mol, 41.91g) to obtain the first reaction liquid,The reaction was heated to reflux for 4h, TLC detected that the reaction was complete, cooled,Pour into a 2mol/L HCl solution, stir for 0.5h, and filter with suction to obtain a solid. After the solid is dissolved in ethanol (EA), it is recrystallized to obtain compound 3 (50 g, yield: 79%).

References:

CN113173872,2021,A Location in patent:Paragraph 0026; 0038-0042