Hydrochloric Acid → HCID 9909321, compound

Participants

Reaction Steps

A mixture of 0.41 gm (1.0 mMol) 3-dimethylamino-9-triisopropylsilyl-1,2,3,4-tetrahydro-9H-carbazole-6-carboxylic acid, 0.77 gm (4.0 mMol) 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 0.54 gm (4.0 mMol) 1-hydroxybenzotriazole, and 0.38 gm (4.0 mMol) 4-aminopyridine in 10 mL dimethylformamide and 50 mL tetrahydrofuran were stirred together at room temperature for 3 days. Polystyrene bound isocyanate resin was added to the reaction mixture which was stirred at 40° C. for 6 hours to scavenge excess 4-aminopyridine. The reaction mixture was filtered, concentrated under reduced pressure and the residue subjected to preparative centrifugal thin layer chromatography (PCTLC), eluting with chloroform containing 5% methanol and 0.5% ammonium hydroxide. Fractions containing the desilylated product were combined and concentrated under reduced pressure to provide a yellow oil. This oil was dissolved in dichloromethane and treated with ethanolic hydrogen chloride. The resulting mixture was concentrated under reduced pressure to provide 0.22 gm (54%) of the title compound as a tan solid.

Provenance & Evidence