反应详情

To a stirred and cooled (-70°~-80° C.) solution of 71.4 parts of a 1-butyllithium solution 1.6M in hexane in 105 parts of 1,1'-oxybisethane was added dropwise a solution of 40.6 parts of 3-bromopyridine in 70 parts of 1,1'-oxybisethane. Upon complete addition, stirring was continued for 15 minutes and a solution of 30 parts of 2-(trifluoromethyl)benzonitrile in 35 parts of 1,1'-oxybisethane was added dropwise at this low temperature. Upon completion, the mixture was stirred for 3 hours at this low temperature. The mixture was heated to room temperature and poured into 84 parts of a hydrochloric acid solution 10N and some crushed ice. The aqueous layer was separated and heated to the boiling point. After cooling, the mixture was made alkaline with an ammonium hydroxide solution and the product was extracted with dichloromethane. The extract was dried, filtered and concentrated. The residue was purified by filtration over silica gel using trichloromethane as eluent. The pure fractions were collected and the eluent was concentrated, yielding 27.8 parts (63%) of (3-pyridinyl) [2-(trifluoromethyl)phenyl]methanone as an oily residue (intermediate 3).

1. additionUpon complete addition
2. stirringstirring
3. stirringUpon completion, the mixture was stirred for 3 hours at this low temperature
4. customThe aqueous layer was separated
5. temperatureheated to the boiling point
6. temperatureAfter cooling
7. extractionthe product was extracted with dichloromethane
8. customThe extract was dried
9. filtrationfiltered
10. concentrationconcentrated
11. filtrationThe residue was purified by filtration over silica gel
12. customThe pure fractions were collected
13. concentrationthe eluent was concentrated