反应详情

A mixture of 3,3-dimethylbutanal (14.5 mL, 115 mmol), 2-methylpropan-1-amine (10.5 mL, 105 mmol) and 10 g of 4 Å molecular sieves (8-12 mesh beads) in acetonitrile (100 mL) was stirred at ambient temperature for 16 h. The material was filtered through Celite with acetonitrile (additional 50 mL) then potassium thiocyanate (13.5 g, 139 mmol) was added to the filtrate and the mixture was warmed to 50° C. Iodine (53.1 g, 209 mmol) was added and the mixture was stirred at 50° C. for 16 h. The mixture was cooled to ambient temperature and then was stirred with sodium metabisulfite (200 mL of 20% aqueous solution) for 1 h at which time the layers were separated. The aqueous layer was extracted with EtOAc (3×15 mL). The combined organics were dried over Na2SO4, filtered, and concentrated under reduced pressure. The crude material was purified by column chromatography (SiO2, 10% MeOH/CH2Cl2 then 9:1:0.1 CH2Cl2:MeOH:NH4OH) to give the title compound (21.5 g, 101 mmol, 97% yield). MS (DCI/NH3) m/z 213 (M+H)+.

1. filtrationThe material was filtered through Celite with acetonitrile (additional 50 mL)
2. temperaturethe mixture was warmed to 50° C
3. stirringthe mixture was stirred at 50° C. for 16 h
4. temperatureThe mixture was cooled to ambient temperature
5. customwere separated
6. extractionThe aqueous layer was extracted with EtOAc (3×15 mL)
7. dry with materialThe combined organics were dried over Na2SO4
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure
10. customThe crude material was purified by column chromatography (SiO2, 10% MeOH/CH2Cl2