反応 #57386

反応方程式

3-(tert-butylamino)-2-(5-(phenylethynyl)-thiophen-2-yl)imidazo[1,2-a]pyrazine-8-carboxylic acid methyl ester

NaOH

DCM hexane

acetic acid

→

3-(tert-butylamino)-2-(5-(phenylethynyl)thiophen-2-yl)imidazo[1,2-a]pyrazine-8-carboxylic acid

収率 44.7%

溶媒

MeOH

MeCN

反応条件

後処理

1. 1
   その他The solvents were then largely removed by distillation under a vacuum
2. 2
   抽出The residual aq. phase was repeatedly extracted with EA
3. 3
   乾燥The combined organic phases were dried over MgSO4
4. 4
   ろ過filtered
5. 5
   その他evaporated under a vacuum

実験手順

A solution of 200 mg (0.47 mmol) of 3-(tert-butylamino)-2-(5-(phenylethynyl)-thiophen-2-yl)imidazo[1,2-a]pyrazine-8-carboxylic acid methyl ester (Example 106) in a mixture of MeOH (5 ml) and MeCN (5.5 ml) was combined with 5 ml (0.51 mmol) of a 0.1M aq. NaOH solution and stirred at RT for 1 h. The reaction mixture was then combined with 26 μl of a 5 N aq. acetic acid solution. The solvents were then largely removed by distillation under a vacuum. The residual aq. phase was repeatedly extracted with EA. The combined organic phases were dried over MgSO4, filtered and evaporated under a vacuum. 87 mg (0.21 mmol, 44%) of 3-(tert-butylamino)-2-(5-(phenylethynyl)thiophen-2-yl)imidazo[1,2-a]pyrazine-8-carboxylic acid were obtained by crystallisation of the group from DCM/hexane (1:2).

出典