反応 #1838902

反応方程式

(2S,5R)-1-(tert-butoxycarbonyl)-5-(hydroxymethyl)pyrrolidine-2-carboxylic acid

n-butyl lithium

dimethyl sulphate

→

clean product

収率 23.0%

(2S,5R)-1-(tert-butoxycarbonyl)-5-(methoxymethyl)pyrrolidine-2-carboxylic acid

収率 23.0%

溶媒

THF

反応条件

後処理

1. 1
   その他was held at −5° C. to 5° C.
2. 2
   その他was held in the −20° C. freezer overnight
3. 3
   その他The reaction was quenched cold, with water
4. 4
   濃縮Next, the mixture was concentrated under reduced pressure
5. 5
   その他to remove THF
6. 6
   抽出extracted with ethyl acetate
7. 7
   乾燥The organic layer was dried over sodium sulphate
8. 8
   ろ過filtered
9. 9
   濃縮concentrated under reduced pressure
10. 10
    その他to give 788 mg crude product, which
11. 11
    その他was then purified by silica gel chromatography

実験手順

A solution of (2S,5R)-1-(tert-butoxycarbonyl)-5-(hydroxymethyl)pyrrolidine-2-carboxylic acid (820 mg, 3.34 mmol) in 11 mL THF was cooled in a −10° C. bath and treated with n-butyl lithium (1.6M in hexanes, 6.5 mL, 10.36 mmol) and kept cold for 1 hour, then dimethyl sulphate (0.380 mL, 4.01 mmol) was added. The temperature was held at −5° C. to 5° C. and then the reaction mixture was held in the −20° C. freezer overnight. The reaction was quenched cold, with water. Next, the mixture was concentrated under reduced pressure to remove THF. The aqueous mixture was acidified with 2N HCl and extracted with ethyl acetate. The organic layer was dried over sodium sulphate, filtered, and concentrated under reduced pressure to give 788 mg crude product, which was then purified by silica gel chromatography to give 199 mg clean product, 140 mg recovered starting material, and 317 mg of a mixture of starting material and product.

出典