CC(=O)N1CCNCC1.COc1ccc(Br)cc1[N+](=O)[O-]>C1COCCO1.CC(=O)O.CC(=O)O.CC1(C)c2cccc(P(c3ccccc3)c3ccccc3)c2Oc2c(P(c3ccccc3)c3ccccc3)cccc21.O=C([O-])[O-].[Cs+].[Cs+].[Pd]>COc1ccc(N2CCN(C(C)=O)CC2)cc1[N+](=O)[O-]1-(piperazin-1-yl)ethanone (9.94 g, 77.58 mmol), Cesium carbonate (50.6 g, 155.15 mmol), XANTPHOS (5.39 g, 9.31 mmol) and Pd(OAc)2 (1.393 g, 6.21 mmol) were added to a stirred solution of 4-bromo-1-methoxy-2-nitrobenzene (18 g, 77.58 mmol) dissolved in dioxane (120 ml). The resulting suspension was heated to 120 °C (bath) over a period of 1 hour. The reaction mixture was allowed to cool and the residual cesium carbonate was removed by filtration through a pad of Dicalite speed plus, washing with dichloromethane. The solvent was removed under reduced pressure to give a dark oil. PBO-02628-53-01 w= 45 g The crude product in solution in DCM was added to a silica gel column and was eluted with methanol 0 to 20% in EtOAc (NOVASEP). Collected fractions to dryness to afford 1-(4-(4-methoxy-3-nitrophenyl)piperazin-1-yl)ethanone (17.96 g, 83 %) as a yellow solid. PBO-02628-53-02
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