Pyridine → 1-(3-Methoxy phenyl)-2-(1-piperazinyl)-indole 3-carboxylic acid (4-methyl)-piperazide

To a solution of 3.2 g (10 mmols) of 2-chloro-1-(3-methoxyphenyl)-indole 3-carboxylic acid chloride in 20 ml of chloroform, a mixture pf 2.2 ml of N-methyl-piperazine, 2.4 ml of pyridine and 5 ml of chloroform was added while cooling. After standing for 1 hour at room temperature, the mixture was washed twice with water, and the solvent was evaporated in vacuo. The resinous residue, which was uniform according to thin-layer chromatography and consisted of 2-chloro-1-(3-methoxyphenyl)-indole 3-carboxylic acid (4-methyl)-piperazide, was dissolved in 40 ml of diglym, and after addition of 13 g (0.15 mol) of piperazine, the solution was heated to the boil. The cooled solution was diluted with methylene chloride, washed three times with water, and the solvent was eliminated in vacuo. The resinous residue was dissolved in chloroform, and an excess of ethanolic hydrochloric acid was added. The solvent was eliminated in vacuo, the crystallized residue was digested with acetone, suction-filtered and washed with acetone. The yield of faintly grey-colored dihydrochloride of the above compound amounted to 3.7 g (73% of the theoretical yield), m.p. 228°-230° C.

1. temperaturewhile cooling
2. washthe mixture was washed twice with water
3. customthe solvent was evaporated in vacuo
4. dissolutionwas dissolved in 40 ml of diglym
5. temperaturethe solution was heated to the boil
6. washwashed three times with water
7. dissolutionThe resinous residue was dissolved in chloroform
8. additionan excess of ethanolic hydrochloric acid was added
9. filtrationsuction-filtered
10. washwashed with acetone
11. customtheoretical yield), m.p. 228°-230° C.

ORD record

ord-2c8b5b82730646d2bf426bb8c3202b96

Source dataset

uspto-grants-1979_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04148895