1,1'-Carbonyldiimidazole → Ethyl alpha-[[(4,5-dihydro-5-thioxo-1,3,4-thiadiazol-2-yl)amino]carbonyl]-3,3-dimethylbutanoate

Beteiligte Stoffe

Reaktionsschritte

To a solution of tert-butylmalonic acid monoethyl ester (3.0 g, 16.0 mmol) in THF (100 mL) is added carbonyldiimidazole (2.85 g, 17.6 mmol) and the reaction is stirred overnight. 5-Amino-(3H)-1,3,4-thiadiazole-2-thione (864 mg, 6.5 mmol) is added and stirring continued for an additional 72 hours. The reaction mixture is 35 poured into pH 4 buffer, extracted with methylene chloride, and the organic layers combined, dried (anhydrous sodium sulfate) and concentrated. Chromatography of the residue on silica gel (elution with 5% methanol/methylene chloride) gave 1.2 g (25%) of the title compound as an amorphous solid.

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