反应 #8853

反应方程式

triethylamine

oxalyl chloride

dimethyl sulfoxide

tert-butyl 4-(3-hydroxy-1-oxopent-1-yl)-4-methoxypiperidine-1-carboxylate

→

title compound

收率 56.6%

tert-Butyl 4-methoxy4-(1,3-dioxopent-1-yl)piperidine-1-carboxylate

收率 56.6%

溶剂

dichloromethane

dichloromethane

反应条件

后处理

1. 1
   其他at −78° C.
2. 2
   workup.WAITAfter 5 min
3. 3
   其他the reaction mixture was removed from the cooling bath
4. 4
   温度to warm to room temperature for 1.5 h
5. 5
   workup.ADDITIONpoured into water
6. 6
   萃取extracted three times with dichloromethane
7. 7
   洗涤washed with brine
8. 8
   干燥dried over sodium sulfate
9. 9
   过滤filtered
10. 10
    浓缩concentrated
11. 11
    其他The residue was purified by flash chromatography
12. 12
    洗涤eluting with 10% ethyl acetate/hexanes

实验过程

To a solution of oxalyl chloride (0.168 mL, 1.92 mmol) in dichloromethane (10 mL) at −78° C. was slowly added dimethyl sulfoxide (0.272 mL, 3.84 mmol). After 5 min, a solution of tert-butyl 4-(3-hydroxy-1-oxopent-1-yl)-4-methoxypiperidine-1-carboxylate (0.404 g, 1.28 mmol) from Step B in dichloromethane (5 mL) was added via syringe. The reaction mixture was stirred for 45 min at -78° C. and then triethylamine (1.1 mL, 7.68 mmol) was added. After 5 min, the reaction mixture was removed from the cooling bath, allowed to warm to room temperature for 1.5 h, poured into water, and extracted three times with dichloromethane. The organic layers were combined, washed with brine, dried over sodium sulfate, filtered, and concentrated. The residue was purified by flash chromatography eluting with 10% ethyl acetate/hexanes to afford the title compound (0.227 g).

来源