4,6-dichloro-2-MethylsulfanylpyriMidine-5-carbaldehyde synthesis

Yield:91759-32-9 95.3%

Reaction Conditions:

Stage #1: thiourea;diethyl propanedioate in methanol at 50 - 70; for 1 h;Autoclave;
Stage #2: with aluminum isopropoxide in methanol at 70 - 80; for 2 h;Autoclave;Reagent/catalyst;Solvent;

Steps:

5 Preparation of 4,6-dihydroxy-2-mercaptopyrimidine

The method comprises the following steps: adding 18.1 g (0.5 mol) of thiourea to the reactor 1 through the material adding pipe,And methanol (organic solvent) 2000ml, heated to about 50 ° C dissolved; and then through this pipe to the reactor1 was added 1,32.1 g (1 mol) of dimethyl malonate, and the autoclave was heated to 60 to 70 ° C;The other tube was charged with 1021.7 g (5 mol) of aluminum isopropoxide to the reactor 1 over a period of 1 hour,70 to 80 ° C for 1 hour; after completion of the reaction, the mixture is slowly cooled to 10 to 20 ° C and stirred for 1 hour to obtainThe reaction solution is passed through a pipe and passed through a filter tank 2, and the filtrate enters the organic solvent recovery tank 5The organic solvent, the waste liquid produced after the recovery of the organic solvent, enters the waste liquid tank 6, and the solidThe body was transferred to acidification tank 3, and 800 ml of water was added to the acidification tank 3, and the temperature was cooled to 0 ° C10 ° C, an organic acid was added to the acidification tank 3 to acidify to pH 5 to 7 and stirred for 1 hourThe resulting liquid was passed through a filter tank 2 and filtered, and the resulting filtrate was passed into an organic solvent recovery tank 5The solvent is recovered and the waste liquid after the recovery of the organic solvent enters the waste liquid tank 6, and the solid transfer in the filter tank 2Dried in a vacuum oven 4 to give 108.8 g of product, yield 95.3%, HPLCAmount of 95.2%.

References:

CN103992279,2016,B Location in patent:Paragraph 0034-0037; 0038-0041; 0059; 0061