HCID 68890897, compound → HCID 68889223, compound

Temperature

0 °C

(R)-7,8-Dichloro-4-methyl-3,4-dihydro-2H-pyrazino[1,2-a]indol-1-one was suspended in toluene and the mixture heated to reflux to remove traces of water. The mixture was cooled to 0° C. (ice-bath) before the addition, via syringe, of borane in tetrahydrofuran. The mixture was stirred 15 min at 0° C., and heated to reflux. After 4 h, the mixture was cooled and excess borane destroyed by the slow addition of a 10% sodium carbonate solution (10 ml). The phases were separated, the aqueous phase extracted with ethyl acetate (2×25 ml), the combined organic phases washed with brine, dried over magnesium sulfate and evaporated. The resulting oil was dissolved in ethyl acetate (5 ml) and a solution of HCl in ethyl acetate added dropwise. The product precipitated out of solution after a short while. It was filtered, washed with a small amount of ethyl acetate and dried to afford the title compound as a white solid (yield 65%).ISP-MS: m/e 255.0 ([M+H]+).

1. temperaturethe mixture heated
2. temperatureto reflux
3. customto remove traces of water
4. additionbefore the addition
5. temperatureheated to reflux
6. waitAfter 4 h
7. temperaturethe mixture was cooled
8. customexcess borane destroyed by the slow addition of a 10% sodium carbonate solution (10 ml)
9. customThe phases were separated
10. extractionthe aqueous phase extracted with ethyl acetate (2×25 ml)
11. washthe combined organic phases washed with brine
12. dry with materialdried over magnesium sulfate
13. customevaporated
14. dissolutionThe resulting oil was dissolved in ethyl acetate (5 ml)
15. additiona solution of HCl in ethyl acetate added dropwise
16. customThe product precipitated out of solution after a short while
17. filtrationIt was filtered
18. washwashed with a small amount of ethyl acetate
19. customdried

ORD record

ord-7a046c568fdf41508bf2bdb5d142411b

Source dataset

uspto-grants-2005_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06844345B2