p-Toluenesulfonic acid → 2-(1-(4-Bromophenyl)-3-oxocyclobutyl)isoindoline-1,3-dione

Participants

Reaction Conditions

Reaction Steps

To a mixture of Compound [XXXVI] (3.25 g, 7.85 mmol, 1.0 eg.) in acetone (300 mL), was added p-toluenesulfonic acid (1.49 g, 7.85 mmol, 1.0 eq.) with stirring and heated to 70° C. After 64 hours at 70° C., the reaction was cooled and poured into saturated aqueous NaHCO3 and extracted with ethyl acetate (×3). The combined organic phases were concentrated and the resulting residue purified by silica gel chromatography eluting with heptane and ethyl acetate (gradient of 0% to 40% ethyl acetate) to give Compound [XXXVII]: 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 3.92-4.01 (m, 2H) 4.20-4.33 (m, 2H) 7.44-7.52 (m, 4H) 7.74 (dd, J=5.37, 3.12 Hz, 2H) 7.84 (dd, J=5.54, 3.00 Hz, 2H).

Provenance & Evidence