Diisopropylamine → 2-(5-Bromo-1-benzofuran-2-yl)ethan-1-ol

Temperature

60 °C

The product from Example 3A (14.95 g, 50 mmol), palladium(ll) acetate (0.11 g, 0.5 mmol), triphenylphosphine (0.26 g, 1.0 mmol), and copper(I) iodide (0.19 g, 1.0 mmol) were combined in isopropyl acetate (100 mL). Nitrogen gas was bubbled through the reaction mixture for about 15 minutes. The mixture was treated with 3-butyn-1-ol (5.6 mL, 75.0 mmol) stirred briefly and then treated with diisopropylamine (42 mL, 300 mmol) slowly over about 10 minutes. After stirring for 2 hours at about 22° C., the mixture was heated at about 60° C. for about 6 hours and then cooled to about 22° C. The reaction mixture was filtered through a pad of Celite® (˜5 g) and the Celite® was washed with isopropyl acetate (˜30 mL). The filtrate was washed with saturated NaHCO3 solution (100 mL, 2×), 10% Na2S2O3 solution (100 mL, 2×), brine (50 mL), dried over Na2SO4, and distilled to dryness. The residue was purified by silica gel column chromatography to provide the title compound (8.7 g, 72% yield). MS DCl (M+NH4)+ m/z at 258,260; 1H NMR(CDCl3at 400 MHz) δ 3.03 (m, 2H), 3.98 (m, 2H), 6.45 (m, 1H), 7.25-7.32 (m, 2H), 7.60 (d, 1H); 13C NMR (CDCl3 at 100 MHz) δ 32.2, 60.6, 103.0, 112.1, 115.4, 122.8, 126.1, 130.4, 153.1, 157.0.

1. customNitrogen gas was bubbled through the reaction mixture for about 15 minutes
2. stirringAfter stirring for 2 hours at about 22° C.
3. temperaturecooled to about 22° C
4. filtrationThe reaction mixture was filtered through a pad of Celite® (˜5 g)
5. washthe Celite® was washed with isopropyl acetate (˜30 mL)
6. washThe filtrate was washed with saturated NaHCO3 solution (100 mL, 2×), 10% Na2S2O3 solution (100 mL, 2×), brine (50 mL)
7. dry with materialdried over Na2SO4
8. distillationdistilled to dryness
9. customThe residue was purified by silica gel column chromatography

ORD record

ord-ee5051a288954e859b7832a7fc01ed34

Source dataset

uspto-grants-2004_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06822101B2