To a solution of 1-(4-fluoro-phenyl)-4-((6bR,10aS)-3-methyl-2,3,6b,9,10,10a-hexahydro-1H,7H-pyrido[3′,4′:4,5]pyrrolo[1,2,3-de]quinoxalin-8-yl)-butan-1-one (99 mg, 0.25 mmol) in THF is added 3.0 M methyl magnesium bromide in ether (0.25 mL, 0.75 mmol) dropwise at 0° C. Upon the completion of the addition of CH3MgBr, the cooling bath is removed and the reaction mixture is stirred at room temperature for 2 hours. Another batch of 3.0 M methyl magnesium bromide in ether (0.25 mL, 0.75 mmol) is added dropwise, and the reaction mixture was stirred at room temperature overnight. The mixture is carefully quenched with water, basified with saturated sodium bicarbonate, and then extracted with methylene chloride four times. The combined organic phase is evaporated to dryness, and the residue is purified on a basic alumina column to give 28 mg of pure product as a white solid. 1H NMR (500 MHz, Chloroform-d) δ 8.22 (br, 1H), 7.58-7.37 (m, 2H), 7.07 (t, J=8.5 Hz, 1H), 7.01 (t, J=8.7 Hz, 1H), 6.65 (dt, J=10.6, 7.7 Hz, 1H), 6.57-6.29 (m, 2H), 3.59 (td, J=11.1, 3.0 Hz, 1H), 3.37-3.12 (m, 4H), 3.00-2.65 (m, 5H), 2.55-2.13 (m, 5H), 2.12-1.78 (m, 4H), 1.69-1.30 (m, 5H). MS (ESI) m/z 410.2 [M+H]+.
