Maleic Anhydride → Dimethyl 5-hydroxy-2-(3-methoxy-3-oxopropyl)pyridine-3,4-dicarboxylate

反応式

C(O[C:4]1[O:8][C:7]([CH2:9][CH2:10][C:11]([O:13][CH3:14])=[O:12])=[N:6][CH:5]=1)C.[C:15]1(=O)[O:20][C:18](=[O:19])[CH:17]=C1.C[Si](C=[N+]=[N-])(C)C.[CH2:29]([O:31][CH2:32][CH3:33])C.Cl.C[OH:36]>>[OH:8][C:4]1[C:17]([C:18]([O:20][CH3:15])=[O:19])=[C:33]([C:32]([O:31][CH3:29])=[O:36])[C:7]([CH2:9][CH2:10][C:11]([O:13][CH3:14])=[O:12])=[N:6][CH:5]=1

参加物

反応物 4

HCID 7923Maleic Anhydride

HCID 21893726Hydrochloride methanol

HCID 23159941trimethylsilyldiazomethane Et2O

HCID 59179423Methyl 3-(5-ethoxy-1,3-oxazol-2-yl)propanoate

生成物 1

HCID 59179398Dimethyl 5-hydroxy-2-(3-methoxy-3-oxopropyl)pyridine-3,4-dicarboxylate収率 30%

実験手順

A mixture of methyl 3-(5-ethoxy-1,3-oxazol-2-yl)propanoate (7.00 g, 35.1 mmol) and maleic anhydride (3.44 g, 35.1 mmol) was stirred at room temperature for 2 hr, 10% hydrochloric acid-methanol solution (100 mL) was added, and the mixture was heated under reflux for 15 hr. The solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (ethyl acetate/methanol=100/0→70/30). The purified product was dissolved in methanol, 2M trimethylsilyldiazomethane/diethyl ether solution (34 mL, 68 mmol) was added at room temperature, and the mixture was stirred for 30 min. The solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (ethyl acetate/hexane=25/75→50/50) to give the title compound (3.10 g, yield 30%).