反応 #12015

反応方程式

sodium bicarbonate

(4R,9aR)-6-bromo-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester

intermediate b

(4R,9aR)-6-bromo-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester

ethyl acrylate

sodium acetate

tri(o-tolyl)phosphine

→

desired compound

収率 91.2%

(4R,9aR)-6-(2-Ethoxycarbonyl-vinyl)-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester

収率 91.2%

溶媒

toluene

反応条件

後処理

1. 1
   温度The reaction mixture was heated
2. 2
   温度under reflux for 20 h
3. 3
   抽出extracted with ethyl acetate
4. 4
   洗浄The organic phase was washed with 10% aqueous citric acid solution and brine
5. 5
   乾燥dried over magnesium sulfate
6. 6
   ろ過filtered
7. 7
   その他evaporated
8. 8
   その他The crude product was purified by column chromatography on silica gel (0.032–0.063 mm) with n-hexane:ethyl acetate (9:1) as eluant

実験手順

To a solution of 1.0 g (2.71 mmol) (4R,9aR)-6-bromo-4-methyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester (Example 5, intermediate b) and 0.36 ml (3.25 mmol) ethyl acrylate in 30 ml toluene were added 0.67 g (8.15 mmol) sodium acetate, 82.6 mg (0.27 mmol) tri(o-tolyl)phosphine and 0.04 mg (0.1 mmol) allylpalladium chloride dimer. The reaction mixture was heated under reflux for 20 h, then poured into saturated aqueous sodium bicarbonate solution and extracted with ethyl acetate. The organic phase was washed with 10% aqueous citric acid solution and brine, dried over magnesium sulfate, filtered and evaporated. The crude product was purified by column chromatography on silica gel (0.032–0.063 mm) with n-hexane:ethyl acetate (9:1) as eluant to afford the desired compound as a yellow solid (91.2%).

出典