The invention discloses a process for preparing a 2,3-di-substituted cyclopentanone mixture containing an enriched cis-2,3-di-substituted cyclopentanone which comprises heating a trans-2,3-di-substituted cyclopentanone in the presence of 100 ppm or less (weight basis) of a metal carbonate based on the cyclopentanone. The invention also discloses a fragrant composition comprising 20 to 50 wt % of 2,3-di-substituted cis-methyl (dihydro)jasmonates and 80 to 50 wt % of 2,3-di-substituted (dihydro) trans-methyl (dihydro)jasmonates. The fragrant composition has jasmine flower-like fragrance.