2H-3-Benzazepin-2-one, 1,3,4,5-tetrahydro- → 2,3,4,5-Tetrahydro-1H-benzo(d)azepine

Temperature

0 °C

A solution of 4,5-dihydro-1H-benzo[d]azepin-2(3H)-one (3.5 mmol) was in THF (25 mL) was stirred at 0° C. for 5 min. A solution of 1M BH3.THF (4 mL) was added dropwise to the reaction mixtureat 0° C. over a period of 30 min. The ice bath was removed and the reaction stirred at RT for 30 min. The reaction mixture was heated at 60° C. overnight, then cooled to 0° C. and additional 1M BH3.THF (2.5 mL) was added dropwise into the reaction mixtureat 0° C. over a period of 15 min. The ice bath was removed and it was stirred at RT for 30 min then heated at 60° C. for 7 h. The reaction mixture was cooled to RT, then further cooled with an ice-bath. The reaction was quenched by the addition of 2M HCl (15 mL). The mixture was heated for 30 min and then 20% NaOH (7.5 mL) was added with ice cooling. The solution was extracted with chloroform (3×) and the organic layer was washed with H2O. The organic layer was dried (Na2SO4), concentrated and redissolved in 2 mL of EtOAc and acidified with 3M HCl/EtOAc. The solid was filtered and dried under vacuum to obtain 2,3,4,5-tetrahydro-1H-benzo[d]azepine as a shiny powder (0.36 g, 69% yield). LC-MS (EI) m/z: 148.2 (M+H+).

1. customThe ice bath was removed
2. stirringthe reaction stirred at RT for 30 min
3. temperatureThe reaction mixture was heated at 60° C. overnight
4. temperaturecooled to 0° C.
5. additionadditional 1M BH3.THF (2.5 mL) was added dropwise into the reaction mixtureat 0° C. over a period of 15 min
6. customThe ice bath was removed
7. stirringit was stirred at RT for 30 min
8. temperaturethen heated at 60° C. for 7 h
9. temperatureThe reaction mixture was cooled to RT
10. temperaturefurther cooled with an ice-bath
11. customThe reaction was quenched by the addition of 2M HCl (15 mL)
12. temperatureThe mixture was heated for 30 min
13. addition20% NaOH (7.5 mL) was added with ice cooling
14. extractionThe solution was extracted with chloroform (3×)
15. washthe organic layer was washed with H2O
16. dry with materialThe organic layer was dried (Na2SO4)
17. concentrationconcentrated
18. dissolutionredissolved in 2 mL of EtOAc
19. filtrationThe solid was filtered
20. customdried under vacuum

ORD record

ord-6842d5dbcf6e4d75b0fb6e9f305e5f80

Source dataset

uspto-grants-2012_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08163756B2