1-Methylpiperazine → HCID 135418433, compound

Ethyl 2-(2-aminoanilino)benzo[b]thiophene-3-carboxylate (3.5 g) and 1-methylpiperazine (20 ml) were dissolved in anisole (50 ml), titanium tetrachloride (3.1 ml) was added dropwise while stirring the mixture at room temperature. After the completion of dropwise addition, the mixture was stirred at 140° C. for 20 hours. The reaction mixture was cooled to 80° C. and poured into ice water. The resultant precipitate was filtrated. The filtrate was extracted with ethyl acetate (900 ml), washed with saturated brine, and dried over MgSO4. The solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/methanol) and the obtained oily substance was dissolved in ethyl acetate (50 ml), to which was added a solution (10 ml) of maleic acid (580 mg) in ethyl acetate. The precipitated crystals were collected by filtration and recrystallized from ethyl acetate/methanol to give 12-(4-methylpiperazin-1-yl)-6H-[1]benzothieno[2,3-b][1,5]benzodiazepine.2 maleate (1.14 g).

1. additionAfter the completion of dropwise addition
2. stirringthe mixture was stirred at 140° C. for 20 hours
3. temperatureThe reaction mixture was cooled to 80° C.
4. filtrationThe resultant precipitate was filtrated
5. extractionThe filtrate was extracted with ethyl acetate (900 ml)
6. washwashed with saturated brine
7. dry with materialdried over MgSO4
8. customThe solvent was evaporated under reduced pressure
9. customThe residue was purified by silica gel column chromatography (ethyl acetate/methanol)
10. dissolutionthe obtained oily substance was dissolved in ethyl acetate (50 ml), to which
11. additionwas added a solution (10 ml) of maleic acid (580 mg) in ethyl acetate
12. filtrationThe precipitated crystals were collected by filtration
13. customrecrystallized from ethyl acetate/methanol

ORD record

ord-5165a6515d7b4b219c7bea13d5692ada

Source dataset

uspto-grants-2002_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06455521B1