[Cl:1][C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=O)=[CH:4][N:3]=1.[NH2:11][C:12]([CH3:17])([CH2:15]O)[CH2:13][OH:14]>>[Cl:1][C:2]1[N:3]=[CH:4][C:5]([C:6]2[O:8][CH2:15][C:12]([CH2:13][OH:14])([CH3:17])[N:11]=2)=[CH:9][CH:10]=1A suspension of 6-chloronicotinic acid (3.2 g, 20.4 mmol) and 2-amino-2-methyl-1,3-propanediol (2.1 g, 20 mmol) in xylenes (mixture of isomers, 80 ml) is heated at reflux under Dean-Stark conditions for 24 h, during which the mixture clarifies. Upon cooling to room temperature, a solid settles down. The mixture is filtered through a silicagel column, eluting first with hexane to remove the xylenes and then with ethyl acetate to afford 1.8 g of [2-(6-chloropyridin-3-yl)-4-methyl-4,5-dihydro-1,3-oxazol-4-yl]methanol ax55.
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