[CH2:1]([Li])[CH2:2][CH2:3][CH3:4].C(NC(C)C)(C)C.[OH:13][C:14]1[N:21]=[C:20](C)[CH:19]=[CH:18][C:15]=1[C:16]#[N:17].C(Br)C=C>C1COCC1>[CH2:1]([C:20]1[CH:19]=[CH:18][C:15]([C:16]#[N:17])=[C:14]([OH:13])[N:21]=1)[CH2:2][CH:3]=[CH2:4]n-Butyllithium (100 mL of a 1.6 M solution in hexanes, 160 mmol, 2.5 equiv) was added via cannula over 10 min to a solution of diisopropylamine (22.4 mL, 160 mmol, 2.5 equiv) in THF (600 mL) at −78° C. The resulting pale yellow solution was stirred at −78° C. for 5 min, then was warmed to 0° C. for an additional 5 min. 2-Hydroxy-6-methylnicotinonitrile (8) (8.58 g, 64.0 mmol, 1 equiv) was added as a solid in small portions over 15 min and the deep orange solution thus obtained was stirred for 1 h at 0° C. Allyl bromide (8.31 mL, 96.0 mmol, 1.5 equiv) was then added and the reaction mixture was warmed to 23° C., maintained at that temperature for 30 min, and was partitioned between 1.0 M HCl (300 mL) and EtOAc (2×250 mL). The combined organic layers were dried over Na2SO4 and were concentrated. The resulting orange solid was triturated with boiling Et2O (100 mL) and subsequently cooled to 23° C., then was filtered through a medium frit, washed with Et2O (2×50 mL) and air-dried to give a1 (6.42 g, 58%) as a tan solid: mp=122-125° C.; IR (KBr pellet, cm−1) 2223, 1654; 1H NMR (DMSO-d6) δ 2.32-2.37 (m, 2H), 2.62 (t, 2H, J=7.6), 4.96-5.06 (m, 2H), 5.69-5.83 (m, 1H), 6.23 (d, 1H, J=7.3), 8.03 (d, 1H, J=7.3), 12.55 (s, br, 1H); Anal. C10H10N2O·0.10H2O: C, H, N.
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