反应详情

To a solution of 6-bromo-7-fluoro-2-phenylchroman-4-one (400 mg, 1.25 mmol) in DCM (10 mL) was added TiCl4 (2.5 mL, 1 M in CH2Cl2) dropwise within 15 minutes at room temperature. After stirring for 1 h, N,N′-methanediylidenebis(1,1,1-trimethylsilanamine) (0.62 mL, 2.75 mmol) was added dropwise. The mixture was stirred at room temperature overnight and poured into ice-water (50 g). The aqueous layer was extracted with CH2Cl2, which was combined with the organic layer. The organic layer was dried and concentrated to give crude N-(6-bromo-7-fluoro-2-phenylchroman-4-ylidene)cyanamide (327 mg, 78%). 1H-NMR (CDCl3): 3.19 (m, 1H), 3.49 (m, 1H), 5.34 (m, 1H), 6.81 (d, 1H), 7.41 (m, 5H), 8.27 (d, 1H).

1. stirringThe mixture was stirred at room temperature overnight
2. extractionThe aqueous layer was extracted with CH2Cl2, which
3. customThe organic layer was dried
4. concentrationconcentrated