Hydrochloric Acid → 9-Acetyl-8-hydroxy-1,2-dihydro-6-(3-dimethylaminopropyl)-cyclopenta[c]carbazole-3-one

Temperature

-40 °C

A 0.5 M solution of BBr3 (16.5 mL, 5 eq.) was added dropwise under argon to a solution of compound 38 (0.658 g, 1.74 mmol) in CH2Cl2 (100 mL) cooled to −40° C. The mixture was kept for 10 min; then a cooling bath was removed and the mixture was heated to room temperature and kept for 1-2 h (TLC monitoring, eluent: CHCl3/NH3-MeOH, 9:1). The resulting mixture was poured in a mixture of aqueous NaHCO3 solution and CH2Cl2. The organic layer was separated; the aqueous one was extracted with CH2Cl2, dried over Na2SO4, evaporated, and dissolved in a mixture: CHCl3-MeOH-water, 40:9:1. The product was purified in a silica gel column with the use of the latter mixture as an eluent. Yield of Example 4: 0.258 g (41%). For the preparation of hydrochloride, the product isolated was dissolved in a mixture: CH2Cl2-MeOH; a solution of HCl in dioxane was added. The resulting mixture was evaporated to dryness; the residue was washed with ether.

1. customthen a cooling bath was removed
2. temperaturethe mixture was heated to room temperature
3. waitkept for 1-2 h
4. additionThe resulting mixture was poured in a mixture of aqueous NaHCO3 solution and CH2Cl2
5. customThe organic layer was separated
6. extractionthe aqueous one was extracted with CH2Cl2
7. dry with materialdried over Na2SO4
8. customevaporated
9. dissolutiondissolved in a mixture
10. customThe product was purified in a silica gel column with the use of the latter mixture as an eluent
11. customFor the preparation of hydrochloride
12. customthe product isolated
13. dissolutionwas dissolved in a mixture
14. customThe resulting mixture was evaporated to dryness
15. washthe residue was washed with ether

ORD record

ord-2df23f1083c8490494d56ab9665e0909

Source dataset

uspto-grants-2014_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08765738B2