9-Fluorenylmethyl chloroformate → 3-Nitrobenzoic acid

Participants

Reaction Steps

4-(Aminomethyl)-3-nitrobenzoic acid G (0.8 g; 4 mmol) was dissolved in 10% aq. Na2CO3 (25 mL) and 1,4-dioxane (10 mL) and the solution was cooled to 0° C. A solution of 9-fluorenylmethyl chloroformate (Fmoc-Cl) (1.06 g; 4 mmol) in 1,4-dioxane (10 mL) was added dropwise for 20 min. After 2 h at 0-5° C. and 1 h at 10° C. the reaction mixture was filtered and the solution was acidified to pH 5 by addition of 1 N HCl. The precipitate was filtered, washed with H2O (2×2 mL) dried under vacuum (1.3 kPa; P2O5) to give 4-[[[9H-fluoren-9-ylmethoxy)carbonyl]amino]methyl]-3-nitrobenzoic acid as a white solid (1.6 g; 3.7 mmol). Yield 92%.

Provenance & Evidence