Cesium carbonate → methyl 4-[4-([[(1R,3S)-3-[[(tert-butoxy)carbonyl]amino]cyclopentyl]sulfanyl]methyl)-5-methyl-1,3-oxazol-2-yl]benzoate

Participants

Reaction Conditions

Reaction Steps

To a solution of methyl 4-[5-methyl-4-(sulfanylmethyl)-1,3-oxazol-2-yl]benzoate (870 mg, 3.30 mmol, 1.00 equiv) in N,N-dimethylformamide (20 mL) maintained under an atmosphere of nitrogen at 35° C. was added cesium carbonate (2.5 g, 7.65 mmol, 2.32 equiv). After stirring at 35° C. for 20 min, tert-butyl N-[(1S,3S)-3-iodocyclopentyl]carbamate (1.25 g, 4.02 mmol, 1.22 equiv) was then added. The resulting solution was allowed to stir for 50 min at 35° C. under nitrogen after which the product was precipitated by the addition of 50 mL water. The solid was collected by filtration, washed with water then dried in a vacuum oven to give 1.35 g (91%) of methyl 4-[4-([[(1R,3S)-3-[[(tert-butoxy)carbonyl]amino]cyclopentyl]sulfanyl]methyl)-5-methyl-1,3-oxazol-2-yl]benzoate as a white solid.

Provenance & Evidence