Ethanol → HCID 13424021, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of (-)-α-methylbenzyl 5-(1-methyl-5-methylthiopyrrol-2-oyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate (3.0 g, 7.1 mmol) in CH2Cl2 (80 ml) at -78° C. under N2 atmosphere was slowly added a 1.0M solution of boron tribromide in CH2Cl2 (15.6 ml, 15.6 mmol). The solution was stirred at -78° C. for 5 minutes and absolute ethanol (30 ml) was added slowly and warmed to room temperature then stirred at room temperature for 2 hours. The solution was washed with water (3×25 ml.) and brine (1×25 ml.), dried over anhydrous sodium sulfate, filtered and rotovapped at 20° C. to an orange solid and chromatographed on a flash silica gel column (5×15 cm) eluted with 50% ether/hexane. The resulting crude product was crystallized from hot EtOH to afford 2.12 g (86% yield) of (-)-ethyl 5-(1-methyl- 5-methylthiopyrrol-2-oyl)-1,2-dihydro-6-methyl-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate. [α]D25 =-127.4 (CHCl3, C=1.06); m.p. 113°-115° C.

Provenance & Evidence