Triethylamine → HCID 57636788, compound

Participants

Reaction Conditions

Reaction Steps

(1S,1aR,7bS)-4,7-difluoro-1,1a,2,7b-tetrahydrocyclopropa[c]chromen-1-carboxylic acid (0.5 g, 2.2 mmol, ˜95% ee) was mixed with toluene (3 ml), triethylamine (0.34 ml, 1.1 eq), DPPA (0.52 ml, 1.1 eq) and bubbled with argon for about 5 min. The reaction mixture was then heated at stirring at 120° C. for 1.5 h under argon. The temperature was then decreased to 50° C. and a mixture of 3 ml of 10% hydrochloric acid in 10 ml dioxane was added. The reaction mixture was stirred for 2 h at 50° C. and then concentrated by rotary evaporation. The residue was mixed with water ant diethyl ether. Water phase was collected and basified with 28% aqueous ammonia to pH 11 and extracted into ether (3×20 ml). Combined organic phases were washed with water and brine and dried over magnesium sulfate. Concentration by rotary evaporation gave 310 mg of crude product as yellow orange oil. The product was purified by column chromatography on silica (30 g, EtOAc/hexane 1:2) to give 220 mg of colorless oil (50% yield).

Provenance & Evidence