[CH2:1]([O:3][C:4](=[O:13])[C:5]1[CH:10]=[C:9]([CH3:11])[N:8]=[C:7](Cl)[CH:6]=1)[CH3:2].C([O-])([O-])=O.[Cs+].[Cs+].[CH:20]([NH2:23])([CH3:22])[CH3:21].CC1(C)C2C(=C(P(C3C=CC=CC=3)C3C=CC=CC=3)C=CC=2)OC2C(P(C3C=CC=CC=3)C3C=CC=CC=3)=CC=CC1=2>O1CCOCC1>[CH2:1]([O:3][C:4](=[O:13])[C:5]1[CH:10]=[C:9]([CH3:11])[N:8]=[C:7]([NH:23][CH:20]([CH3:22])[CH3:21])[CH:6]=1)[CH3:2]
To a solution of 2-chloro-6-methyl-isonicotinic acid ethyl ester (5.20 g, 26.0 mmol) in dioxane (200 mL), Cs2CO3 (25.5 g, 78.1 mmol) and isopropylamine (9.24 g, 156.3 mmol) is added. The mixture is degassed and put under N2 before Xantphos (5.43 g, 9.38 mmol) and Pd(II) acetate (1.17 g, 5.26 mmol) are added. The mixture is stirred in a sealed vessel at 85° C. for 18 h. The mixture is cooled to rt, filtered and concentrated. The crude product is purified by CC on silica gel eluting with heptane:EA 7:3 to give 2-isopropylamino-6-methyl-isonicotinic acid ethyl ester (3.91 g) as an orange solid; LC-MS: tR=0.67 min; [M+1]+=223.10.
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