Dimethylformamide → 6-Isopropoxypicolinaldehyde

反応式

Br[C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([O:8][CH:9]([CH3:11])[CH3:10])[N:3]=1.C([Li])CCC.CN([CH:20]=[O:21])C>C1COCC1>[CH:9]([O:8][C:4]1[N:3]=[C:2]([CH:20]=[O:21])[CH:7]=[CH:6][CH:5]=1)([CH3:11])[CH3:10]

参加物

反応条件

温度: -78 °C

実験手順

6-isopropoxypyridine-2-carbaldehyde was prepared in a manner similar to that described in D. L. Comins, M. O. Killpack, J. Org. Chem. 1990 55 69-73 for the methoxy analog. 2-bromo-6-isopropoxypyridine (1 g, 4.6 mmole) was dissolved in 10 ml dry THF under argon, cooled to −78° C. and treated with added 2.5 M n-Butyl lithium (1.9 mL, 4.8 mmole) keeping the temperature of the reaction below −65° C. After the reaction had stirred 45 min DMF (0.717 mL, 9.25 mmole) was added, again keeping temp below −60° C., the reaction was stirred for 15 min, then quenched with saturated bicarbonate solution. The layers were separated, the aqueous extracted with CHCl3, the organic layers dried over Na2SO4, filtered and evap carefully, and the residue chromatographed in 0-50% Ether/hexanes to give the product as an oil. LCMS (m+1)=165.2