1-(5-Methyl-2-pyridinyl)ethanone

2-Acetyl-5-methylpyridine is an aromatic ketone.

5-(5-Methyl-2-pyridyl)-1-(2-pyridyl)-1H-pyrazole-3-carboxylic acid; [Show Image] 1) 1-(5-Methyl-2-pyridyl)ethanone; n-Butyllithium (1.58M solution in hexane, 24 ml) was added to a solution of 2-bromo-5-picoline (5.0 g) in diethylether (100 ml) in 5 minutes at -78°C, and the mixture was stirred for 5 minutes. N, N-Dimethyl acetamide (3.5 ml) was added to the reaction liquid at the same temperature, and the mixture was stirred for 2 hours. Water and ethyl acetate were added to the reaction liquid and the phases were separated, and the organic layer was dried over anhydrous magnesium sulfate. After filtration, the solvent was evaporated under reduced pressure, and the residue was purified by column chromatography on silica gel (hexane-ethyl acetate) to give 1-(5-methyl-2-pyridyl)ethanone (3.43 g, 87percent) as an oily product. 1) 2) 1-(5-Methyl-2-pyridyl)-1-ethanone n-Butyllithium (a 1.58 M solution in hexane, 24 mL) was added dropwise to a solution of 2-bromo-5-picoline (5.0 g) in diethyl ether (100 mL) over 5 minutes under cooling to -78°C, and then the resultant mixture was stirred for 5 minutes. N, N-dimethylacetamide (3.5 mL) was added dropwise to the reaction solution, and then the mixture was stirred for 2 hours. Water and ethyl acetate were added to the reaction solution, and the mixture was partitioned. The organic layer was dried over anhydrous magnesium sulfate. After separation by filtration, a residue obtained by evaporating the solvent under reduced pressure was purified by silica gel column chromatography (hexane-ethyl acetate), to obtain 1-(5-methyl-2-pyridyl)-1-ethanone (3.43 g, 87percent) as an oily product. To a solution of 2-bromo-5-methyl pyridine 23 (1.73 g, 10 mmol) in dry ether (20 ml), cooled to -78 [00219] l-(5-methylpyridin-2-yl)-ethanone (51)[00220] To a solution of 2-bromo-5 -methyl pyridine 49 (1.73 g, 10 mmol) in dry ether (20 ml), cooled to -78 Into a 250 ml three-necked flask, 4.8 g of 5-methyl-2-ethyl-pyridine (40 mmol) and 60 ml of nitrobenzene (1.205 g/ml) are added and refluxed at 110° C. for about 50 h. After the removal of nitrobenzene at a pressure lower than 10 mmHg, a black viscous liquid substance is obtained. The mixed solution of ethyl acetate and petroleum ether with a volume ratio of 1:2 is used as an eluent to make silica gel column chromatography on the black viscous liquid substance, and a colorless liquid with a weight of 1.6 g and a yield of 30percent is obtained. The product is identified as 5-methyl-2-acetyl-pyridin by Mass Spectrometry. (0160) Mass Spectrometry MS-EI: 135Concentration gave 48.5 g of a yellow oil which was distilled to give 28.3 g of product b.p. 66-67 C./1.7-1.8 mm (Lit. b.p. 92-95/15 mm).General procedure: 2 mol/L hydrochloric acid (0.5 mL) was added to a solution of 4-(difluoromethyl)-2-(1-ethoxyvinyl)pyrimidine (13 mg) obtained in Reference Example 22-15 (5) in acetone (0.75 mL), followed by stirring at room temperature for 1.5 hours. Saturated sodium hydrogen carbonate aqueous solution and a saturated sodium chloride aqueous solution were added to the reaction mixture, and the resultant product was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure, whereby 1-(4-(difluoromethyl)pyrimidin-2-yl)ethanone was obtained. (1326) MS(ESI m/z): 173 (M+H) (1327) RT(min): 0.69

Molecular Weight:135.16
XLogP3:1.2
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:1
Exact Mass:135.068413911
Monoisotopic Mass:135.068413911
Topological Polar Surface Area:30
Heavy Atom Count:10
Complexity:133
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes