General procedure for the synthesis of 4-fluoroisoindoline hydrochloride from the compound (CAS: 685565-16-6): to a solution of compound 3 (56 g, 0.246 mol) in methanol (300 mL) was slowly added concentrated hydrochloric acid (30 mL, 0.36 mol) and 5% Pd/C catalyst (20 g). The reaction mixture was placed under hydrogen atmosphere and stirred at room temperature for 48 hours. Upon completion of the reaction, the catalyst was removed by filtration and the filtrate was concentrated to afford the target product 4-fluoroisoindoline hydrochloride as a yellow solid (38 g, 89% yield). The product was characterized as follows: 1H NMR (300 MHz, D2O): δ 1M-1.22 (m, 1H), 7.00-7.03 (m, 1H), 6.88-6.94 (m, 1H), 4.50-4.52 (d, 4H). lc-MS: 138 (M + H)+.
