Triethylamine → N-[(1S,1aR,7bR)-4,7-difluoro-1,1a,2,7b-tetrahydrocyclopropa[c]chromen-1-yl]-N'-(3-isoxazolyl)urea

Participants

Reaction Conditions

Reaction Steps

(1S,1aR,7bS)-4,7-difluoro-1,1a,2,7b-tetrahydrocyclopropa[c]chromene-1-carboxylic acid (50 mg, 0.22 mmol, ee˜90%) was mixed with toluene (1 ml), triethylamine (0.034 ml, 1.1 eq), 3-aminoisoxazole (0.018 ml, 1.1 eq), DPPA (0.054 ml, 1.1 eq). The reaction mixture was then heated at stirring at 110° C. for 3 h. The reaction mixture was concentrated by rotary evaporation and purified by column chromatography on silica (50 g, ethylacetate/hexane 1:1) to give 10 mg of the product as white solid.

Provenance & Evidence