反应详情

2,5-dimethylphenylmagnesium bromide (84 g, 20% solution in tetrahydrofuran) is added dropwise over five hours to a refluxing solution of 4-bromo-2-methylbenzonitrile (16 g), palladium (II) chloride (0.57 g) and triphenylphosphine (1.7 g) in tetrahydrofuran (100 ml). [HPLC: yield 90-95%]. After cooling to room temperature tetrahydrofuran is removed under vacuum. The residue is taken up in toluene/water (1:1) (200 ml) and filtered. The aqueous phase is separated off, and the solvent removed by distillation. The crude product is recrystallised from ethanol to give 3,2',5'-trimethylbiphenyl-4-carbonitrile as a solid, m.pt. 96-97° C. 1H NMR (CDCl3): 2.19(s,3H), 2.34(s,3H), 2.58(s,3H), 6.99(s,1H), 7.08-7.25(m,3H), 7.62(d,1H).

1. customis removed under vacuum
2. filtrationfiltered
3. customThe aqueous phase is separated off
4. customthe solvent removed by distillation
5. customThe crude product is recrystallised from ethanol