[Li]CCCC.[NH2:6][C:7]1[CH:12]=[CH:11][C:10]([CH3:13])=[CH:9][N:8]=1.[Si:14]([O:21][CH:22]([CH2:28][CH2:29][CH2:30][CH3:31])[C:23](OCC)=[O:24])([C:17]([CH3:20])([CH3:19])[CH3:18])([CH3:16])[CH3:15].O>C1COCC1.CCOC(C)=O>[Si:14]([O:21][CH:22]([CH2:28][CH2:29][CH2:30][CH3:31])[C:23]([NH:6][C:7]1[CH:12]=[CH:11][C:10]([CH3:13])=[CH:9][N:8]=1)=[O:24])([C:17]([CH3:20])([CH3:19])[CH3:18])([CH3:15])[CH3:16]n-BuLi (2.25 mL, 1.6 M in hexanes, 3.60 mmol) was added slowly to a stirred solution of 2-amino-5-picoline (390 mg, 3.60 mmol) in anhydrous THF (6 mL). The reaction mixture was kept at ambient temperature for 10 minutes before it was added to a solution of ethyl 2-{[tert-butyl(dimethyl)silyl]oxy}hexanoate (Step 1) (820 mg, 3.00 mmol) in anhydrous THF (4 mL). The reaction mixture was stirred at ambient temperature for 1 h. Water and EtOAc were added and the two phases were separated. The organic phase was washed with water, dried over MgSO4 and concentrated in vacuo. The residue was purified with column chromatography (silica gel, eluting with a gradient consisting of 0-100% EtOAc in heptane) to give the title compound as a colourless oil (223 mg), 1H NMR (300 MHz, CDCl3) δ 8.87 (br s, 1H), 8.13 (m, 2H), 7.51 (dd, 1H), 4.25 (t, 1H), 2.29 (s, 3H), 1.79 (m, 2H), 1.35 (m, 4H), 0.98 (s, 8H), 0.89 (t, 3H), 0.14 (d, 6H).
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