Ethyl propiolate → (S)-2-(4-tert-butyl-phenoxymethyl)-2,3-dihydro-oxazolo[3,2-a]pyrimidin-7-one

Participants

Reaction Steps

To a solution of (S)-5-(4-tert-butyl-phenoxymethyl)-4,5-dihydro-oxazol-2-ylamine (4.53 g, 18.3 mmol) in ethanol (35 mL) was added ethyl propiolate (2.32 g, 23.7 mmol). The reaction mixture was stirred at reflux for 6 hours. The mixture was stirred at 30° C. for a few minutes and subsequently cooled to room temperature. The resulting crystals were collected and washed twice with hexane. The solid was dried under high vacuum at 65° C. for 18 hours to afford 2.8 g (50%) of (S)-2-(4-tert-butyl-phenoxymethyl)-2,3-dihydro-oxazolo[3,2-a]pyrimidin-7-one. [α]D25 −54.04 (c 0.503, CHCl3).

Provenance & Evidence