[CH3:1][C:2]1([CH3:9])[CH2:7][CH2:6][CH2:5][CH:4]([OH:8])[CH2:3]1.C[Si]([N-][Si](C)(C)C)(C)C.[Na+].Cl[C:21]1[CH:26]=[CH:25][C:24]([C:27]#[N:28])=[CH:23][N:22]=1>C1COCC1>[CH3:1][C:2]1([CH3:9])[CH2:7][CH2:6][CH2:5][CH:4]([O:8][C:21]2[N:22]=[CH:23][C:24]([C:27]#[N:28])=[CH:25][CH:26]=2)[CH2:3]1Dissolve 3,3-dimethylcyclohexanol (6 g, 47 mmoles) in anhydrous THF (70 mL) under nitrogen atmosphere and cool at −78° C. Add sodium bis(trimethylsilyl)amide (23.4 mL, 47 mmol, 2M solution in THF) to this solution and stir at −78° C. for 30 min before raising to room temperature. Cool down again to −78° C. and add a solution of 2-chloro-5-cyanopyridine (7.1 g, 51.7 mmoles) in anhydrous THF (20 mL) and stir overnight while warming to room temperature. Add saturated aqueous NaHCO3 (100 mL) and extract the aqueous layer with DCM (3×100 mL). Wash the combined organic extracts with brine (200 mL). Dry over MgSO4, filter and concentrate in vacuo. Purify the crude mixture by chromatography on silica gel eluting with cyclohexane/EtOAc (1:0 to 9:1 gradient) to afford the desired intermediate as a solid (9.14 g, 84%). MS (ES+) m/z: 231.1 (M+H)+.
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