反応 #48169

反応方程式

4-(3-methyl-4-nitro-phenoxy)-piperidine-1-carboxylic acid tert-butyl ester

4-(3-Methyl-4-nitro-phenoxy)-piperidine-1-carboxylic acid tert-butyl ester

diethyloxalate

potassium tert-butylate

ethanol

hydrochloric acid

→

4-[3-(2-Ethoxycarbonyl-2-oxo-ethyl)-4-nitro-phenoxy]-piperidine-1-carboxylic acid tert-butyl ester

溶媒

tetrahydrofuran

tetrahydrofuran

反応条件

後処理

1. 1
   抽出The aqueous phase was extracted 3 times with tert-butylmethylether
2. 2
   洗浄the combined organic phases were washed with brine
3. 3
   乾燥dried over sodium sulfate
4. 4
   ろ過filtered
5. 5
   その他evaporated to dryness in vacuo
6. 6
   その他crystallized from ethanol
7. 7
   その他to yield 44.09 g (81%) as white crystals

実験手順

A solution of 4-(3-methyl-4-nitro-phenoxy)-piperidine-1-carboxylic acid tert-butyl ester (example 43, step 1, 41.9 g, 1.0 eq.) and diethyloxalate (18.77 mL, 1.1 eq.) in tetrahydrofuran (241.7 mL) was dropped into a cold (0-5° C.) solution of potassium tert-butylate (28.54 g, 2.0 eq.) and ethanol (43.64 mL, 6.0 eq.) in tetrahydrofuran (1.022 L). The mixture was stirred for 3 h at 0-5° C. and for 18.5 h at room temperature, poured into 1M hydrochloric acid solution. The aqueous phase was extracted 3 times with tert-butylmethylether and the combined organic phases were washed with brine, dried over sodium sulfate, filtered, evaporated to dryness in vacuo and crystallized from ethanol to yield 44.09 g (81%) as white crystals. MS (m/e): 436.2 (M, 5%).

出典