反应详情

Titanium tetrachloride (0.50 mL, 4.53 mmol) was slowly added to a slurry of zinc powder (0.61 g, 9.31 mmol) in dry tetrahydrofuran (10 mL). The reaction mixture was heated at reflux for 2.5 h. A solution of 3,3,5,5-tetramethyl-cyclohexanone (0.64 mL, 3.67 mmol) and N-[4-(4-methoxy-benzoyl)-phenyl]-benzenesulfonamide (182) (0.45 g, 1.22 mmol) in dry tetrahydrofuran (10 mL) was added to the reaction mixture and heated at reflux for another 2 h. The reaction mixture was cooled to room temperature and diluted with water (10 mL) followed by 10% K2CO3 (10 mL). The reaction mixture was filtered through a pad of Celite and the pad was washed with EtOAc. The filtrate was transferred to a separatory funnel and the layers were separated. The aqueous layer was extracted with EtOAc and the combined organic layers were washed with brine, dried over Na2SO4, filtered, and concentrated. The crude material was purified by flash chromatography on silica gel with a hexanes:EtOAc gradient (100:0 to 55:45) to give 0.48 g (80%) of compound 183 as a white powder. 1H NMR (400 MHz, DMSO-d6): δ 0.81 (s, 6H), 0.84 (s, 6H), 1.21 (s, 2H), 1.75, (s, 2H), 1.85 (s, 2H), 3.68 (s, 3H), 6.79 (d, J=8.6 Hz, 2H), 6.95-6.98 (m, 6H), 7.47-7.50 (m, 2H), 7.55-7.58 (m, 1H), 7.69 (d, J=7.3 Hz, 2H), 10.17 (s, 1H).

1. temperatureThe reaction mixture was heated
2. temperatureat reflux for 2.5 h
3. temperatureheated
4. temperatureat reflux for another 2 h
5. filtrationThe reaction mixture was filtered through a pad of Celite
6. washthe pad was washed with EtOAc
7. customThe filtrate was transferred to a separatory funnel
8. customthe layers were separated
9. extractionThe aqueous layer was extracted with EtOAc
10. washthe combined organic layers were washed with brine
11. dry with materialdried over Na2SO4
12. filtrationfiltered
13. concentrationconcentrated
14. customThe crude material was purified by flash chromatography on silica gel with a hexanes