Hydrochloric Acid → HCID 67434643, compound

Participants

Reaction Steps

The (S)—N1-(2-aminoethyl)-3-(4-nitrophenyl)propane-1,2-diamine trihydrochloride salt was synthesized following the procedures of Brechbiel and Meares (Brechbiel, M. W. et al. Inorg. Chem. 1986, 25, 2772; Meares, C. F. Bioconjugate Chem. 2000, 11, 292.). The HCl salt of the methyl ester of para-nitrobenzylalanine (p-NO2Bn-Ala-OMe, HCl salt, 13.03 g, 50 mmoles, 1 eq.) was dissolved in methanol (30 mL) and triethylamine (10.5 mL, 75 mmoles, 1.5 eq.) was added. The reaction mixture was stirred for 15 minutes at RT and ether (225 mL) was added. The reaction mixture was cooled to 0° C. with an ice-bath and the precipitate was filtered off and rinsed with ether (20 mL). The filtrate was concentrated to an orange oil which was re-dissolved in methanol (10 mL) and the solution of free amine was added at RT to ethylenediamine (100 mL, 1500 mmoles, 30 eq.) via a syringe pump over 4 h under argon. The mixture was stirred for 11 h and the ethylenediamine and the methanol were evaporated under high vacuum to give the desired crude amide (13.16 g, 104%) as a brown oil which was used directly in the next step without any further purification.

Provenance & Evidence