Toluene → 6'-Bromospiro[cyclohexane-1,2'-indene]-1',4(3'H)-dione

Participants

Reaction Conditions

Reaction Steps

6-Bromo-2,3-dihydro-1H-inden-1-one (800 g, 3.79 mol) and methyl acrylate (787 mL, 8.72 mol) in 2-methyl-tetrahydrofuran (4 L) were stirred at 28° C. Potassium tent-pentoxide solution in toluene (1.7 M, 2.68 L, 4.55 mol) was added dropwise keeping the temperature between 30° C. and 43° C. The mixture was stirred for 0.5 h at 25° C. Water (4 L) was added and after 10 min were KOH (383 g, 6.82 mol) added. The mixture was heated to reflux and the organic solvent was distilled off during 4 h. The mixture was cooled to 10° C., and the formed precipitate was filtered off and dried in vacuo to give the title compound (837 g, 75% yield). 1H NMR (500 MHz, DMSO-d6) δ ppm 1.74-1.85 (m, 2 H), 1.94 (m, 2 H), 2.34 (m, 2 H), 2.52-2.60 (m, 2 H), 3.27 (s, 2 H), 7.60 (d, 1 H), 7.79-7.83 (m, 1 H), 7.89 (m, 1 H); MS (ES+) m/z 293 [M+H]+.

Provenance & Evidence