Ammonia → HCID 59581287, compound

Participants

Reaction Steps

To a suspension of tert-butyl (2-{[(4S)-3-methyl-2,5-dioxo-1′,3′-dihydrospiro[imidazolidine-4,2′-inden]-5′-yl]amino}-2-oxoethyl)carbamate from Step A (1.80 g, 4.63 mmol) in EtOAc (50 mL), at 0° C., was added anhydrous HCl (bubbled in through a pipet, for 5 minutes). After an additional 30 minutes of standing at 0° C., the solvent and excess HCl was removed in vacuo to yield a solid. This solid was then dissolved in the minimal amount of MeOH and treated with a methanolic 2 N ammonia solution (20 mL, 40 mmol). This mixture was stirred for 30 min at ambient temperature, before the bulk of the MeOH was removed in vacuo. The residue was applied to a silica gel column for purification, eluting with DCM:MeOH (10% conc. NH4OH)—95:5 to 85:15. Product containing fractions were pooled and concentrated in vacuo to give the title compound. MS: m/z=289 (M+1).

Provenance & Evidence