B1(B2OC(C)(C)C(C)(C)O2)OC(C)(C)C(C)(C)O1.C([O-])(=O)C.[K+].Br[C:25]1[CH:26]=[N:27][C:28]([N:31]2[C:39]3[C:34](=[CH:35][CH:36]=[C:37]([C:40]([N:42]4[CH2:46][CH2:45][CH2:44][CH2:43]4)=[O:41])[CH:38]=3)[C:33]([S:47][CH3:48])=[CH:32]2)=[N:29][CH:30]=1.Br[C:50]1[CH:55]=[C:54]([CH:56]2[CH2:58][CH2:57]2)[CH:53]=[CH:52][N:51]=1.C(=O)([O-])[O-].[K+].[K+]>O1CCOCC1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.Cl[Pd]Cl.[Fe+2].C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[CH:56]1([C:54]2[CH:53]=[CH:52][N:51]=[C:50]([C:25]3[CH:30]=[N:29][C:28]([N:31]4[C:39]5[C:34](=[CH:35][CH:36]=[C:37]([C:40]([N:42]6[CH2:43][CH2:44][CH2:45][CH2:46]6)=[O:41])[CH:38]=5)[C:33]([S:47][CH3:48])=[CH:32]4)=[N:27][CH:26]=3)[CH:55]=2)[CH2:58][CH2:57]1Bis(pinacolato)diboron (0.584 g, 2.3 mmol) and potassium acetate (0.421 g, 4.29 mmol) were added at room temperature to a solution of 341a) (0.6 g, 1.43 mmol) in dry dioxane (35 mL). The reaction apparatus was flushed with argon, PdCl2(dppf) (58 mg, 0.071 mmol) was added and the resulting mixture was stirred for 1 h at 110° C. (complete consumption of starting material). 2-bromo-4-cyclopropyl-pyridine (0.328 g, 2.14 mmol), potassium carbonate (2M, 2.5 mL) and tetrakis(triphenylphosphine)palladium(0) (83 mg, 0.071 mmol) were added successively and the reaction mixture was stirred for 16 h at 100° C. The mixture was then cooled to ambient temperature and filtered through a sintered funnel. The filtrate was concentrated and the remnant was purified by flash column chromatography [silica; dichloromethane with 2% methanol]. White solid. Yield: 0.28 g (43% of theory)
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