反応 #3212

反応方程式

dimethyl 4,7-dichloroquinoline-2,3-dicarboxylate

sodium formate

water

→

solid

収率 134.8%

Dimethyl 7-chloroquinoline-2,3-dicarboxylate

収率 134.8%

溶媒

dimethylformamide

反応条件

後処理

1. 1
   温度was heated at 90°-95° C. for 7 hr
2. 2
   その他was degassed
3. 3
   workup.ADDITIONan additional quantity of tetrakis(triphenylphosphine)palladium(0) (0.92 g, 0.80 mM) was added
4. 4
   温度the reaction mixture again heated at 90°-95° C. for 6 hr
5. 5
   その他The cooled reaction mixture
6. 6
   抽出the resulting mixture extracted with ethyl acetate
7. 7
   乾燥The combined extracts were dried (MgSO4)
8. 8
   ろ過filtered
9. 9
   濃縮concentrated

実験手順

A stirred mixture of dimethyl 4,7-dichloroquinoline-2,3-dicarboxylate (5.00 g, 15.9 mM), sodium formate (1.63 g, 23.9 mM) and tetrakis(triphenylphosphine)palladium(0) (0.92 g, 0.80 mM) in anhydrous dimethylformamide (75 mL) under a nitrogen atmosphere was heated at 90°-95° C. for 7 hr. No reaction occurred so the reaction mixture was degassed and an additional quantity of tetrakis(triphenylphosphine)palladium(0) (0.92 g, 0.80 mM) was added and the reaction mixture again heated at 90°-95° C. for 6 hr. The cooled reaction mixture was poured into water and the resulting mixture extracted with ethyl acetate. The combined extracts were dried (MgSO4), filtered and concentrated to leave an gummy solid (6.0 g). Trituration of this residue with ethyl acetate and subsequent filtration separated a crystalline solid which was shown to be dimethyl 7-chloro-4-hydroxyquinoline-2,3-dicarboxylate. The filtrate was concentrated and the residue was flash chromatographed over silica gel (eluant: hexane/ethyl acetate, 3/2) to provide the title diester (1.13 g, 25.4%) as a light yellow crystalline solid; MS(CI): 280 (M+H).

出典