5-[5-(2-Chloroacetyl)-2-ethoxyphenyl]-1,6-dihydro-1-Methyl-3-propyl-7H-pyrazolo[4,3-d]pyriMidin-7-one synthesis

Yield: 89.6%

Reaction Conditions:

Stage #1:chloroacetyl chloride with aluminum (III) chloride at 20; for 0.166667 h;Green chemistry;Industrial scale;
Stage #2:5-(2-ethoxy)-phenyl-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidine-7-oneGreen chemistry;Industrial scale;

Steps:

2.1 (1) Compound (B) Preparation of 5- [2-ethoxy-5- (chloromethyl-1-ylcarbonyl)] phenyl-1-methyl-3-n-propyl-1,6-dihydro -7H-pyrazolo [4,3-d] pyrimidin-7-one
180g (1.592mol) of chloroacetyl chloride was put into a dry 500ml reaction flask, and the reaction solution was cooled to below 20 ° C. 125g (0.9370mol) of anhydrous aluminum trichloride was put into batch at 20 , and the mixture was stirred for 10 minutes.After the reaction was completed, the reaction solution was cooled to below 20 ° C by ice water, 55.72g (0.1785mol) of compound (A) was put into the reaction flask in batches, and the feed rate was controlled so that the internal temperature did not exceed 20 ° C.Casting completed, the reaction was stirred at 45-50 4h.After the reaction is completed, the reaction liquid is added back to the ice-water mixture until the solid material is completely precipitated, filtered, and the solid material is collected and washed with water to a pH value of 4-5, filtered and dried to obtain 62.2g of a white solid material.Namely compound (B). Yield: 89.6% (calculated as Compound A).

References:

Wang Jinglin;Liu Guizhen;Yu Ruimei;Zeng Qingmei;Li Yang;Wang Song CN104650093, 2017, B Location in patent:Paragraph 0020; 0045; 0046