Molbank, Vol. 2017, Article M966: (±)-Methyl 1,1a,2,7b-Tetrahydro-2-oxocyclopropa[c] Chromene-1a-carboxylate (Molbank)

A novel method for the preparation of (±)-methyl 1,1a,2,7b-tetrahydro-2-oxocyclopropa[c]chromene-1a-carboxylate has been developed. The cyclopropanation of methyl coumarin-3-carboxylate provided title compound in moderate yield by dropwise treatment with 1.5 equiv. of dimethylsulfoxonium methylide over 6 h. The structure of the newly synthesized compound was determined using 1H-, 13C-NMR, IR and mass spectral data.