1,2,4,5-Tetrazine-3,6-dicarboxylic acid, 1,2-dihydro-, dimethyl ester

Dimethyl dihydro-1,2,4,5-tetrazine-3,6-dicarboxylate 1,2,4,5-Tetrazine-3,6-dicarboxylic acid, 1,2-dihydro-, dimethyl ester (9) (3787-10-8)... 

The submitters employed, without purification, thionyl chloride obtained from Fisher Scientific Company. The procedure should be performed in a well-ventilated hood since thionyl chloride Is a lachrymator. The yield of dimethyl ester was found to be lower in instances when the thienyl chloride-methanol solution was not allowed to stir (30 min, -30°C) prior to the addition of dihydro-1,2,4,5-tetrazine-3,6-dicarboxylic acid. 

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