[CH2:1]([O:3][C:4](=[O:17])[C:5]1[CH:10]=[C:9]([N:11]([CH2:14][CH3:15])[CH2:12][CH3:13])[N:8]=[C:7](Cl)[CH:6]=1)[CH3:2].[CH3:18][Zn]Cl>O1CCOCC1.O>[CH2:1]([O:3][C:4](=[O:17])[C:5]1[CH:6]=[C:7]([CH3:18])[N:8]=[C:9]([N:11]([CH2:14][CH3:15])[CH2:12][CH3:13])[CH:10]=1)[CH3:2]To a solution of 2-chloro-6-diethylamino-isonicotinic acid ethyl ester (10.1 g, 31.6 mmol) in dioxane (120 mL), Pd(dppf) (262 mg, 0.322 mmol) is added. MeZnCl (8.40 g, 72.4 mmol) is added dropwise to the mixture before it is stirred at 75° C. for 18 h. The mixture is carefully diluted with water, then extracted with EA. The combined org. extracts are dried over MgSO4, filtered and concentrated. The crude product is purified by CC on silica gel eluting with heptane:EA 9:1 to give 2-diethylamino-6-methyl-isonicotinic acid ethyl ester (6.39 g, containing some methyl ester) as a pale yellow oil; LC-MS: tR=0.70 min, [M+H]+=237.11.
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