Br[C:2]1[CH:3]=[C:4]([CH3:7])[S:5][CH:6]=1.C(N(CC)CC)C.[CH3:15][C:16]1([CH3:23])[C:20]([CH3:22])([CH3:21])[O:19][BH:18][O:17]1>C1COCC1.CC(P[Pd]PC(C)(C)C)(C)C>[CH3:15][C:16]1([CH3:23])[C:20]([CH3:22])([CH3:21])[O:19][B:18]([C:2]2[CH:3]=[C:4]([CH3:7])[S:5][CH:6]=2)[O:17]1To 4-bromo-2-methylthiophene (1.5 g, 8.5 mmol) in THF (17 ml) was added bis[(1,1-dimethylethyl)phosphanyl]palladium (218 mg, 0.43 mmol), then N,N-diethylethanamine (2.5 g, 25.4 mmol) and 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1.63 g, 12.7 mmol) and the resulting mixture heated at 40° C. under argon for 2 hours. The reaction was cooled and then filtered, washing with tert-butyl methyl ether. The washings were reduced in vacuo and the residue purified by chromatography on silica gel (gradient of hexane to 3% ethyl acetate:hexane) to afford the title compound (D38). MS (ES+) m/e 225 [M+H]+.
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