3,4-Dimethoxyphenyl methyl ketone → 4-[1-(3,4-Dimethoxyphenyl)ethyl]piperazine

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Reaction Steps

A quantity of 0.17 g (0.6 mmole, 1 eq) of 1-(4-chloro-3-trifluoromethyl-phenyl)-piperazine and 0.1 g (0.6 mmole, 1 eq) of 3,4-dimethoxyacetophenone and 2 mL of Ti(OiPr)4 are warmed to 70° C. for 2 hours. The reaction solution is cooled to room temperature and 20 mL of anhydrous methanol is added followed by 1.0 g of NaBH4 and the resulting solution is stirred at room temperature for 2 hours. The reaction is quenched by the addition of 1 N NaOH and extracted with CH2Cl2. The CH2Cl2 extracts are dried over anhydrous MgSO4 and concentrated in vacuo. The residue is chromatographed on SiO2 with ethyl to afford 1-[4-chloro-3-trifluoromethyl)phenyl]-4-[1-(3,4-dimethoxyphenyl)ethyl]piperazine (compound 2). Analysis 1H NMR (400 MHz, CDCl3): 7.31 (1H, d), 7.19 (1H, m), 6.90 (4H, m), 3.89 (6H, d), 3.38 (1H, m), 3.20 (4H, m), 2.61 (4H, m). MS (LC-MS): Calculated for C21H24ClF3N2O2 428.88, found 429.30 (M+). III. 3-{1-4-(4-Bromo-3-methoxy-phenyl)-piperazin-1-yl]-ethyl}-quinoline via Scheme C

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