Hydrochloric Acid → Carbamic acid, (4-oxobutyl)-, 9H-fluoren-9-ylmethyl ester

Participants

Reaction Steps

To a stirring solution of N-Fmoc-4-amino-butyraldehyde diethyl acetal (0.050 mmol) in 1,4-dioxane (100 mL) was added aq. HCl (100 ml, 1:1 v/v, H2O: conc. HCl) and the reaction progress was monitored by MS. Upon completion, the organic solvent was removed by rotary evaporation, and the aqueous layer was extracted with ethyl acetate (2×200 mL). The combined organic layers were washed with 5% NaHCO3 (2×75 mL), brine (75 mL), dried over Na2SO4, filtered and concentrated to dryness to yield the desired N-Fmoc-4-amino-butyraldehyde (15.35 g, 0.049 mol, 90.0% yield), which was carried through to the next step without further purification: MS m/e [M+Na]+ calcd 332.1, found 332.0.

Provenance & Evidence