Reaktion #78997

Reaktionsgleichung

6-(3-bromo-phenyl)-4,4-dimethyl-1,4-dihydro-benzo[d][1,3]oxazin-2-one

trimethylsilylacetylene

→

title compound

Ausbeute 92.0%

4,4-Dimethyl-6-(3-trimethylsilanylethynyl-phenyl)-1,4-dihydro-benzo[d][1,3]oxazin-2-one

Ausbeute 92.0%

Lösungsmittel

triethyl amine

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction mixture was cooled to rt
2. 2
   Sonstigethe solvent was removed
3. 3
   Waschenwashed with 1N aqueous HCl (3×20 mL) and brine (20 mL)
4. 4
   SonstigeThe organic layer was separated
5. 5
   Trocknendried (MgSO4)
6. 6
   SonstigeAfter removal of solvent
7. 7
   Sonstigethe residue was purified by a silica gel chromatography (hexane:ethyl acetate/3:1)

Vorschrift

A mixture of 6-(3-bromo-phenyl)-4,4-dimethyl-1,4-dihydro-benzo[d][1,3]oxazin-2-one (0.8 g, 2.4 mmol), trimethylsilylacetylene (1 g, 10 mmol), tetrakis(triphenylphosphine)palladium (0) (0.17 g, 0.24 mmol), and cuprous (I) iodide (0.05 g, 0.28 mmol) in triethyl amine (20 mL) was heated under nitrogen at 80° C. for 3 hours. The reaction mixture was cooled to rt and the solvent was removed. The residue was taken up in ethyl acetate (50 mL) and washed with 1N aqueous HCl (3×20 mL) and brine (20 mL). The organic layer was separated and dried (MgSO4). After removal of solvent, the residue was purified by a silica gel chromatography (hexane:ethyl acetate/3:1) to afford the title compound as a white solid (0.77 g, 92%): mp 240-242° C.; 1H-NMR (DMSO-d6) δ 10.3 (s, 1H), 7.74-7.69 (m, 2H), 7.61-7.58 (m, 2H), 7.48-7.40 (m, 2H), 6.96 (d, 1H, J=7.98 Hz), 1.67 (s, 6H), 0.25 (s, 9H); MS (EI) m/z 349([M+], 50%); Anal. Calc. For C21H23NO2Si.0.2 EtOAc: C, 71.32; H, 6.75; N, 3.82. Found: C, 71.08; H, 6.64; N, 3.82.

Quelle