反应详情

A mixture of 1,1,2,2-tetrafluoro-6-(trans-4-propylcyclohexyl)-1,2-dihydronaphthalene and 1,1,2,4-tetrafluoro-6-(trans-4-propylcyclohexyl)-1,2-dihydronaphthalene, 10.0 g (30.6 mmol) in THF was stirred with zinc dust (10 g, 153 mmol) and aqueous 30% NH40H at ambient temperature. After 27 h, GC analysis showed that the mixture contained <1% of the starting material. The mixture was filtered, and the zinc was washed with hexanes. The filtrate was transferred to a separatory funnel, the phases were separated, and the solvent was evaporated from the organic phase. The weight of product recovered was 8.6 g. GC analysis of the product showed that it contained 0.9% 1,1,2,2-tetrafluoro-6-(trans-4-propylcyclohexyl)-1,2-dihydronaphthalene, 13.4% 1,2,4-trifluoro-6-(trans-4-propylcyclohexyl)naphthalene, and 82% 1,2-difluoro-6-(trans-4-propylcyclohexyl)naphthalene. This example shows that when ammonia is not buffered to reduce the pH, more by-products are formed compared to the reaction in which buffered ammonia is used (Example 8).

1. filtrationThe mixture was filtered
2. washthe zinc was washed with hexanes
3. customThe filtrate was transferred to a separatory funnel
4. customthe phases were separated
5. customthe solvent was evaporated from the organic phase
6. customThe weight of product recovered
7. customare formed