Diisopropylethylamine → HCID 178451167, Verbindung

0.321 g of cis-6-(4-tert-butoxycarbonylcyclohexyloxy)nicotinic acid (1 mmol, 1 eq.) is placed in 50 mL of acetonitrile at room temperature. 0.33 mL of diisopropylethylamine (2 mmol, 2 eq.), 0.466 g of bromotris-pyrrolidinophosphonium hexafluorophosphonate (1 mmol, 1 eq.) and 0.270 g of 5-(3-chlorobenzyl)[1.3.4]thiadiazol-2-ylamine (1.2 mmol, 1.2 eq.) are successively added with stirring. After 4 days at room temperature, the reaction medium is evaporated and 15 mL of DMF are added. The medium is stirred again for 18 hours, diluted in ethyl acetate, washed three times with brine, dried over magnesium sulfate, filtered and evaporated. The residue is chromatographed on silica gel, eluting with a gradient of ethyl acetate in heptane ranging from 5% to 50%. After evaporating the fractions of interest, the residue is chromatographed on silica gel with a gradient of ethyl acetate in dichloromethane ranging from 2% to 20%. 0.262 g of tert-butyl cis-4-{5-[5-(3-chlorobenzyl)[1.3.4]thiadiazol-2-ylcarbamoyl]pyridin-2-yloxy}cyclohexanecarboxylate is obtained.