Br[C:2]1[CH:7]=[CH:6][C:5]([O:8][CH3:9])=[CH:4][CH:3]=1.[CH3:10][CH:11]([CH3:28])[CH2:12][CH2:13][N:14]1[CH:18]=[C:17](B2OC(C)(C)C(C)(C)O2)[CH:16]=[N:15]1.C(=O)([O-])[O-].[K+].[K+].O>O1CCCC1.C1C=CC(P([C]2[CH][CH][CH][CH]2)C2C=CC=CC=2)=CC=1.C1C=CC(P([C]2[CH][CH][CH][CH]2)C2C=CC=CC=2)=CC=1.Cl[Pd]Cl.[Fe]>[CH3:9][O:8][C:5]1[CH:6]=[CH:7][C:2]([C:17]2[CH:16]=[N:15][N:14]([CH2:13][CH2:12][CH:11]([CH3:28])[CH3:10])[CH:18]=2)=[CH:3][CH:4]=1To p-bromoanisole (0.25 g, 1.33 mmol) was added a solution of 1-(3-methylbutyl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (0.41 g, 1.55 mmol) in tetrahydrofuran (10 ml), potassium carbonate (0.29 g, 2.1 mmol) and [1,1-bis(diphenylphosphino)ferrocene]dichloropalladium (II) (12 mg, 0.023 mmol) and the mixture refluxed under nitrogen for 17 h. Water (50 ml) was added to the reaction mixture and stirring continued at RT for 15 min followed by extraction with ether (2×50 ml), drying (MgSO4) and evaporation of the ether extract to give a brown oil (0.414 g). Purification by column chromatography (silica gel, 100% chloroform) afforded 4-(4-methoxyphenyl)-1-(3-methylbutyl)-1H-pyrazole (12) as a waxy pale yellow solid (37 mg, 11%). 1H nmr (CDCl3, 300 MHz) 0.97, d (6.6 Hz), 2×Me; 1.64, sept (6.6 Hz), H3″; 1.80, dt (7.2 Hz), H2″; 3.82, s, OMe; 4.15, t (7.5 Hz), H1″; 6.90, d (8.7 Hz), H3′,5′; 7.39, d (8.7 Hz), H2′,6′; 7.54, s, H3 or H5; 7.69, s, H5 or H3. ESI (+ve) MS m/z 245 (M+H, 100%).
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