1-(3,5-dichlorophenyl)propan-1-one

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of 3,5-dichloropropiophenone (8m, 3.81 g, 0.0188 mol) in CH2Cl2 (28 mL) was added bromine (0.986 mL, 19.1 mmol) dropwise. The bromine was immediately consumed upon addition of each drop until the end of addition when it had a consistent brownish color, indicative of excess bromine. The reaction was immediately quenched with saturated aqueous NaHCO3, extracted three times with CH2Cl2. The organic layer was separated, combined and concentrated under reduced pressure, without drying to afford a yellow oil. The oil was dissolved in anhydrous diethyl ether (50 mL) and 2-amino-2-methyl-1-propanol (6.7 g, 0.075 mol) was added. The reaction mixture was stirred overnight and quenched with saturated aqueous NaHCO3. The aqueous layer was extracted three times with CH2Cl2, and the organic layers concentrated to afford another yellow oil. Purification by column chromatography on silica gel afforded 2.51 g (46%) of the title compound. The hemi-fumarate salt was prepared by dissolving the free base in methanol and adding 1.0 g of fumaric acid to form the title compound: mp 188-190° C.; 1H NMR (DMSO-d6) δ 7.58-7.57 (m, 1H), 7.47 (m, 2H), 6.67 (s, 0.5H), 4.09 (d, 1H, J=11.9 Hz), 3.53 (d, 1H, J=12.0 Hz), 3.41-3.37 (m, 1H), 1.53 (s, 3H), 1.28 (s, 3H), 1.02 (d, 3H, 6.6 Hz); 13C NMR (DMSO-d6) δ 134.9, 133.6, 127.7, 125.2, 94.7, 67.2, 52.5, 50.1, 25.0, 21.6, 14.6; Anal. (C15H19Cl2NO4.0.25H2O) calcd: C, 51.08; H, 5.57; N, 3.97. found: C, 51.13; H, 5.64; N, 3.90. The bromine was immediately consumed upon addition of each drop until the end of addition when it The reaction was immediately quenched with saturated aqueous NaHCO3 extracted three times with CH2Cl2 The organic layer was separated concentrated under reduced pressure without drying to afford a yellow oil quenched with saturated aqueous NaHCO3 The aqueous layer was extracted three times with CH2Cl2 the organic layers concentrated to afford another yellow oil Purification by column chromatography on silica gel