反応 #80451

反応方程式

thiophene

4-fluorobenzyl bromide

n-butyllithium

hexane

→

2-(4-fluorophenylmethyl)thiophene

収率 81.0%

溶媒

THF

ether

THF

反応条件

後処理

1. 1
   その他transferred by cannula into a -78° C.
2. 2
   workup.STIRRINGThe reaction mixture was stirred at ambient temperature under nitrogen overnight
3. 3
   その他quenched with saturated NH4Cl solution (100 mL)
4. 4
   その他partitioned between ether and additional NH4Cl solution
5. 5
   乾燥The ether layer was dried over MgSO4
6. 6
   濃縮concentrated in vacuo
7. 7
   workup.DISTILLATIONthe residue subjected to vacuum distillation

実験手順

A solution of thiophene (12.6 g, 0.15 mol) in a mixture of anhydrous ether (230 mL) and anhydrous THF (70 mL) was treated dropwise at 0° C. with a 2.5M solution of n-butyllithium in hexane (54.0 mL, 0.134 mol). The mixture was stirred at 0° C. for 1.5 hours and then transferred by cannula into a -78° C. solution of 4-fluorobenzyl bromide (23.6 g, 0.125 mol) containing tetrakis(triphenylphosphine) palladium(0) (1.25 g) in anhydrous THF (200 mL). The reaction mixture was stirred at ambient temperature under nitrogen overnight and then quenched with saturated NH4Cl solution (100 mL) and partitioned between ether and additional NH4Cl solution. The ether layer was dried over MgSO4, concentrated in vacuo and the residue subjected to vacuum distillation to give 19.4 g (81% ) of 2-(4-fluorophenylmethyl)thiophene. b.p. 74°-83° C. at 0.6-0.7 mm of Hg.

出典