反応 #1693

反応方程式

2-cyano-5-(hydroxymethyl)thiophene

triphenylphosphine

carbon tetrabromide

→

2-cyano-5-(bromomethyl)thiophene

収率 75.0%

溶媒

THF

反応条件

後処理

1. 1
   その他the solvent was removed in vacuo
2. 2
   workup.DISSOLUTIONthe residue was dissolved in chloroform
3. 3
   洗浄The product was eluted
4. 4
   workup.ADDITIONFractions containing pure product (as judged by TLC)
5. 5
   濃縮concentrated in vacuo

実験手順

To a solution of 2-cyano-5-(hydroxymethyl)thiophene (6.0 g, 43 mmol) in THF (50 mL) was added triphenylphosphine (15.7 g, 47 mmol) and carbon tetrabromide (12.3 g, 47 mmol). After stirring overnight under nitrogen atmosphere at room temperature, the solvent was removed in vacuo and the residue was dissolved in chloroform, then adsorbed onto silica gel and loaded onto a silica gel column. The product was eluted using an ethyl acetate/hexanes gradient. Fractions containing pure product (as judged by TLC) were pooled and concentrated in vacuo to give 6.5 g (75%) of 2-cyano-5-(bromomethyl)thiophene.

出典