METHYL 5-(CHLOROSULFONYL)-4-METHYL-2-THIOPHENECARBOXYLATE synthesis

Yield:423768-46-1 49%

Reaction Conditions:

with chlorosulfonic acid at 20; for 4 h;Cooling with ice;

Steps:

3.1 Example 3 Step one: 4-methyl thiophene-2-carboxylic acid methyl ester by reaction with the chlorosulfonic acid sulphochlorination, to obtain 5-chlorosulfonyl-4-methyl-2-thiophene carboxylic acid methyl ester.

Specific reaction formula is as follows: Under ice bath, the 4-methyl thiophene-2-carboxylic acid methyl ester (3.0g, 19 . 2mmol) instillment to chlorosulfonic acid (10 ml) in, the reaction system is slowly restored to the room temperature, reaction 4h, TLC tracking reaction, after the end of the reaction is complete, the reaction solution slowly poured into 100 ml ice water, dichloromethane is used for extraction, drying, evaporating solvent under reduced pressure, to obtain the product 5-chlorosulfonyl-4-methyl-2-thiophene carboxylic acid methyl ester 1.5g, grey solid, yield is 49%.

References:

CN105237523,2016,A Location in patent:Paragraph 0108; 0109; 0110; 0111; 0112