反应详情

To a solution of 2-amino-5-ethoxy-4-trifluoromethyl-benzonitrile from step 4 (31.62 g, 137.4 mmol) in dry THF (410 mL) was added isoamyl nitrite (40.4 mL, 302 mmol), and the mixture was refluxed for 16 h. The solvent was removed in vacuum to give an orange oil, which was dissolved in sat. NaHCO3-sol., extracted three times with diethyl ether. The combined organic layers were washed with 1 N HCl and brine, dried over Na2SO4. Removal of the solvent in vacuum left an orange oil, which was purified by double Kugelrohr distillation (up to 160° C. bath temperature at 1.5 mbar) to give the title compound as a light yellow solid (25.06 g, 85%). MS (EI) 185.1 [M].

1. temperaturethe mixture was refluxed for 16 h
2. customThe solvent was removed in vacuum
3. customto give an orange oil, which
4. extraction, extracted three times with diethyl ether
5. washThe combined organic layers were washed with 1 N HCl and brine
6. dry with materialdried over Na2SO4
7. customRemoval of the solvent in vacuum
8. waitleft an orange oil, which
9. distillationwas purified by double Kugelrohr distillation (up to 160° C. bath temperature at 1.5 mbar)