反応 #2014

反応方程式

N-(t-Butoxycarbonyl)-D-tryptophan

potassium carbonate

allyl bromide

→

desired product

収率 56.0%

N-(t-Butoxycarbonyl)-D-tryptophan Allyl Ester

収率 56.0%

溶媒

acetone

反応条件

後処理

1. 1
   その他the acetone was substantially removed by evaporation under reduced pressure
2. 2
   抽出extracted with methylene chloride
3. 3
   乾燥The methylene chloride layer was dried over anhydrous magnesium sulfate powder
4. 4
   ろ過filtered
5. 5
   その他evaporated under reduced pressure
6. 6
   その他to give a foamy solid
7. 7
   その他The foam was further purified by column chromatography

実験手順

N-(t-Butoxycarbonyl)-D-tryptophan (3 g; 9.868 mmol) was dissolved in acetone and an aqueous solution of potassium carbonate (2.84 g; 20.58 mmol) added followed by allyl bromide (1.55 g; 12.81 mmol). The reaction mixture was stirred for 18 h and then the acetone was substantially removed by evaporation under reduced pressure. The oily water layer that remained was acidified to approximately pH=5 with 1N-hydrochloric acid and then extracted with methylene chloride. The methylene chloride layer was dried over anhydrous magnesium sulfate powder, filtered and evaporated under reduced pressure to give a foamy solid. The foam was further purified by column chromatography using silica gel and ethyl acetate and hexanes 2:1 v/v as eluant. In this manner, a 1.92 g yield (56%) of the desired product was obtained as an off white solid. FAB-MS:- calculated for C19H24N2O4 344; found 344 (M).

出典