Reaktion #78983

Reaktionsgleichung

3-(4,4-dimethyl-2-oxo-1,4-dihydro-2H-benzo[d][1,3]oxazin-6-yl)benzonitrile

trimethylsilyl azide

dibutyl tin oxide

→

4,4-dimethyl-6-[3-(1H-tetrazol-5-yl)-phenyl]-1,4-dihydrobenzo[d][1,3]-oxazin-2-one

Ausbeute 26.0%

Lösungsmittel

dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas heated
2. 2
   Temperaturat reflux under a blanket of nitrogen
3. 3
   SonstigeUpon completion of the reaction
4. 4
   Sonstigethe dioxane was removed
5. 5
   Waschenwashed with NaHCO3 (100 mL)
6. 6
   Extraktionextracted with ethyl acetate (100 mL)
7. 7
   TrocknenThe organic layer was dried over MgSO4
8. 8
   Einengenconcentrated
9. 9
   SonstigeCrystallization from ether (20 mL)

Vorschrift

A mixture of 3-(4,4-dimethyl-2-oxo-1,4-dihydro-2H-benzo[d][1,3]oxazin-6-yl)benzonitrile (0.77 g, 2.8 mmol), trimethylsilyl azide (0.68 g, 5.6 mmol), and dibutyl tin oxide (0.071 g, 0.28 mmol) in dioxane (20 mL) was heated at reflux under a blanket of nitrogen. Upon completion of the reaction, the dioxane was removed, the organics taken up in ethyl acetate (100 mL), and washed with NaHCO3 (100 mL). The aqueous layer was acidified with 1 N aqueous HCl and extracted with ethyl acetate (100 mL). The organic layer was dried over MgSO4, and concentrated. Crystallization from ether (20 mL) gave 4,4-dimethyl-6-[3-(1H-tetrazol-5-yl)-phenyl]-1,4-dihydrobenzo[d][1,3]-oxazin-2-one as a light yellow solid (0.23 g, 26%): mp 238-240° C.; 1H-NMR (DMSO-d6) δ 10.4 (s, 1H), 8.3 (bs, 1H), 8.02 (d, 1H, J=7.66 Hz), 7.9 (d, 1H, J=7.91 Hz), 7.72-7.65 (m, 3H), 7.03 (d, 1H, J=8.75 Hz), 1.70 (s, 6H); MS (ESI) m/z 320 ([M−H]−, 100%), Anal. Calc. For C17H15N5O2: C, 63.54; H, 4.71; N, 21.79. Found: C, 62.16; H, 4.67; N, 21.31.

Quelle