Br[C:2]1[S:6][C:5]([CH2:7][CH:8]([CH3:10])[CH3:9])=[N:4][CH:3]=1.C([Li])CCC.CCCCCC.C(O[B:26]1[O:30][C:29]([CH3:32])([CH3:31])[C:28]([CH3:34])([CH3:33])[O:27]1)(C)C>C1COCC1>[CH2:7]([C:5]1[S:6][C:2]([B:26]2[O:30][C:29]([CH3:32])([CH3:31])[C:28]([CH3:34])([CH3:33])[O:27]2)=[CH:3][N:4]=1)[CH:8]([CH3:10])[CH3:9]
To a solution of 5-bromo-2-isobutylthiazole (2.10 g, 9.54 mmol) in THF (20 mL) was added 1.6 M n-butyllithium in hexane solution (7.15 mL, 11.44 mmol) dropwise over 45 minutes at −78° C. The resulting solution was stirred at −78° C. for 10 minutes. Then the 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (2.13 g, 11.44 mmol) was added to the above solution and stirred at −78° C. for 1.5 hours. The reaction was quenched with 1:1 saturated ammonium chloride and water and warmed up to close to room temperature. The resulting mixture was extracted with ethyl acetate, washed with water, brine and concentrated. The residue was subjected to flash column chromatography using 30% ethyl acetate/hexane to give a yellow oil (454 mg, 18% yield). 1H NMR, 400 MHz, CDCl3: δ 8.13 (s, 1 H), 2.95 (d, J=7.1 Hz, 2 H), 2.10-2.19 (m, 1 H), 1.36 (s, 12 H), 1.00 (d, J=6.6 Hz, 6 H).
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