Diisopropylethylamine → Tert-butyl (4-{4-[5-(4-fluorobenzyl)[1.3.4]thiadiazol-2-ylcarbamoyl]phenyl}cyclohexyl)acetate

Participants

Reaction Steps

0.3 g of 4-(4-tert-butoxycarbonylmethylcyclohexyl)benzoic acid (0.94 mmol, 1 eq.) is placed in a mixture of 5 mL of dichloromethane and 2 mL of dimethylformamide at room temperature. 0.394 g of 5-(4-fluorobenzyl)-1,3,4-thiadiazol-2-amine (1.88 mmol, 2 eq.), 1.054 g of bromotris-pyrrolidinophosphonium hexafluorophosphonate (2.26 mmol, 2.4 eq.) and 0.66 mL of diisopropylethylamine (3.76 mmol, 4 eq.) are successively added. The reaction mixture is stirred for 6 days at room temperature, diluted in ethyl acetate, washed with saturated aqueous ammonium chloride solution, and washed twice with water and once with brine. The organic phase is concentrated and the residue is chromatographed on silica gel, eluting with a gradient of ethyl acetate in heptane ranging from 10% to 33%. 0.35 g of tert-butyl (4-{4-[5-(4-fluorobenzyl)[1.3.4]thiadiazol-2-ylcarbamoyl]phenyl}cyclohexyl)acetate is obtained.

Provenance & Evidence