CS(C)=O.C(Cl)(=O)C(Cl)=O.[CH2:11]([C:13]1[CH:18]=[CH:17][CH:16]=[C:15]([CH2:19][CH3:20])[C:14]=1[C:21]1[N:26]=[CH:25][C:24]([CH2:27][OH:28])=[C:23]([O:29][CH2:30][CH3:31])[CH:22]=1)[CH3:12]>C(Cl)Cl.C1COCC1.CCOCC>[CH2:11]([C:13]1[CH:18]=[CH:17][CH:16]=[C:15]([CH2:19][CH3:20])[C:14]=1[C:21]1[N:26]=[CH:25][C:24]([CH:27]=[O:28])=[C:23]([O:29][CH2:30][CH3:31])[CH:22]=1)[CH3:12]A solution of dry DMSO (2.5 g, 32 mmol) in CH2Cl2 (2 mL) is added dropwise to a solution of oxalyl chloride (2M in CH2Cl2, 7.5 mL) in CH2Cl2 (80 mL) at −78° C. After 10 minutes, a solution of [6-(2,6-diethyl-phenyl)-4-ethoxy-pyridin-3-yl]-methanol (3.4 g, 11.4 mmol) in THF (20 mL) is added to the above mixture. Fifteen minutes after addition, TEA (10 mL) is added and the mixture is stirred at −78° C. for 15 minutes and then warmed to room temperature. The mixture is diluted with ether (100 mL) and washed with water (2×50 mL). The organic layer is dried and concentrated. The crude product is purified on a silica gel column (4:1 Hexane/EtOAc) to give 6-(2,6-diethyl-phenyl)-4-ethoxy-pyridine-3-carbaldehyde. 1H NMR (CDCl3) 10.53 (s, 1H), 8.98 (s, 1H), 7.30 (t, 1H), 7.15 (d, 2H), 6.89 (s, 1H), 4.20 (q, 2H), 2.34 (m, 4H), 1.54 (t, 3H), 1.06 (t, 9H).
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