반응 #81572
ord-6c498a30fa2a4903a117265bd6877f9c
용매
반응 조건
후처리
- 1기타at 0° C
- 2workup.ADDITIONWhen addition
- 3온도The solution was cooled at 0° C.
- 4workup.STIRRINGstirred at room temperature for 24 hours
- 5workup.ADDITIONThe mixture was poured into ice
- 6추출extracted with ether
- 7건조dried (MgSO4)
- 8기타the solvent evaporated
- 9workup.ADDITIONThe crude product was then treated under the same conditions as above
실험 절차
In a typical experiment, 2 g (0.024 mole) of thiophene in 50 ml THF (dried over sodium) were treated with 2.5 eq. 1.5M n-BuLi in hexane (0.06 mole, 45 ml) at 0° C. When addition was completed, the mixture was stirred at room temperature for 5 hours. The solution was cooled at 0° C., quenched with 9.5 ml (0.06 mole) of 1-bromoheptane and then stirred at room temperature for 24 hours. The mixture was poured into ice, extracted with ether, dried (MgSO4), and the solvent evaporated. The crude product contains mono and disubstituted thiophene in the ratio 1:2 (by 1H-nmr). The crude product was then treated under the same conditions as above to yield exclusively 2,5-diheptylthiophene (5.1 g, 76%) bp 225°/0.1 mm. 1H-nmr (CDCl3) shows 86.5 (s, 2H); 2.7 (t, 4H); 0.75-2.0 (M, 26H).