反応 #8844

反応方程式

lithium diisopropylamide mono(tetrahydrofuran)

methyl 4-(1-(tert-butoxycarbonyl)-4-(methoxycarbonyl)piperidin-4-yl)butanoate

Methyl 4-(1-(tert-butoxycarbonyl)-4-(methoxycarbonyl)piperidin-4-yl)butanoate

lithium diisopropylamide mono(tetrahydrofuran)

ammonium chloride

ethyl acetate

→

title compound

収率 110.2%

tert-Butyl 2-(methoxycarbonyl)-1-oxo-8-azaspiro[4.5]decane-8-carboxylate

収率 110.2%

溶媒

tetrahydrofuran

—

hexanes

反応条件

後処理

1. 1
   workup.STIRRINGthe reaction mixture was stirred for 20 min
2. 2
   抽出extracted three times with diethyl ether
3. 3
   洗浄washed with brine
4. 4
   乾燥dried over sodium sulfate
5. 5
   濃縮concentrated

実験手順

To a solution of methyl 4-(1-(tert-butoxycarbonyl)-4-(methoxycarbonyl)piperidin-4-yl)butanoate (20.1 g, 0.058 mol) from Step E in tetrahydrofuran (600 mL) at −78° C. was added lithium diisopropylamide mono(tetrahydrofuran) (47 mL, 0.070 mol, 1.5M solution in cyclohexanes). The reaction mixture was stirred at −78° C. for 25 min. Thin layer chromatography (tlc) analysis (50% ethyl acetate in hexanes) showed that starting material remained. Additional lithium diisopropylamide mono(tetrahydrofuran) (31 mL) was added and the reaction mixture was stirred for 20 min. The reaction mixture was poured into saturated ammonium chloride and extracted three times with diethyl ether. The organic layers were combined, washed with brine, dried over sodium sulfate, and concentrated to afford the title compound (19.9 g) which was taken on to the next step without further purification.

出典