反应详情

To a mixture of 7-vinylchroman-4-one (Preparation 2D, 0.370 g, 2.12 mmol) and morpholine (0.925 mL, 10.6 mmol) in toluene (8 mL) at 0° C. was added titanium(IV) chloride (1.0 M in toluene) (1.17 mL, 1.17 mmol) dropwise. The ice-bath was removed, and the orange, heterogeneous reaction mixture was stirred at room temperature overnight. The reaction mixture was filtered under reduced pressure through a pad of CELITE®, which was rinsed with toluene (3×10 mL). The pale yellow filtrate was concentrated under reduced pressure to give 4-(7-vinyl-2H-chromen-4-yl)morpholine (0.448 g, 1.84 mmol, 87% yield) as a yellow oil. 1H NMR (500 MHz, CDCl3) δ ppm 2.85-2.90 (m, 4), 3.84-3.89 (m, 4), 4.71 (d, J=4.16 Hz, 2), 5.10 (t, J=4.16 Hz, 1), 5.27 (d, J=11.37 Hz, 1), 5.76 (d, J=17.48 Hz, 1), 6.67 (dd, J=17.62, 10.96 Hz, 1), 6.98-7.03 (m, 2H), and 7.29 (s, 1H).

1. customThe ice-bath was removed
2. filtrationThe reaction mixture was filtered under reduced pressure through a pad of CELITE®, which
3. washwas rinsed with toluene (3×10 mL)
4. concentrationThe pale yellow filtrate was concentrated under reduced pressure