[NH2:1][C:2]1[CH:7]=[CH:6][C:5]([Br:8])=[CH:4][N:3]=1.C([Li])CCC.Cl[Si:15]([CH3:23])([CH3:22])[CH2:16][CH2:17][Si:18](Cl)([CH3:20])[CH3:19]>O1CCCC1>[Br:8][C:5]1[CH:6]=[CH:7][C:2]([N:1]2[Si:18]([CH3:20])([CH3:19])[CH2:17][CH2:16][Si:15]2([CH3:23])[CH3:22])=[N:3][CH:4]=1A solution of 2-amino-5-bromopyridine (5.00 g, 28.90 mmol) was dissolved in tetrahydrofuran (80 mL), cooled to −78° C., and then treated with a 2.5M solution of n-butyllithium in hexanes (11.68 mL, 29.20 mmol). The resulting reaction mixture was stirred for 1 h, at which time, a solution of 1,2-bis(chlorodimethylsilyl)ethane (6.22 g, 28.90 mmol) in tetrahydrofuran (15 mL) was added dropwise to the reaction. The reaction mixture was stirred for another 90 min at −78° C. and then was treated with another portion of a 2.5M solution of n-butyllithium in hexanes (11.68 mL, 29.20 mmol). The reaction was slowly warmed to 25° C. where it was stirred for 2 h. The reaction was then quenched by the addition of a saturated aqueous sodium chloride solution (50 mL) and then extracted with diethyl ether (2×200 mL). The combined organic layers were dried over magnesium sulfate, filtered, and concentrated in vacuo. Kugelrohr distillation at 125–135° C. at 0.5 mmHg afforded 5-bromo-2-(2,2,5,5-tetramethyl-[1,2,5]azadisilolidin-1-yl)-pyridine (5.38 g, 59%) as a white solid: mp 50.4–55.8° C.
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