4-Nitrobenzoic Acid → 3-(4-Nitro-benzoyloxy)-hexahydro-pyrrolo[3,2-b]pyrrole-1,4-dicarboxylic acid 4-benzyl ester 1-tert-butyl ester

Participants

Reaction Steps

To a solution of bicyclic alcohol 11 (4.0 g, 11.0 mmol) in benzene (55 mL) at ambient temperature was added Ph3P (5.8 mg, 22.1 mmol) and p-nitrobenzoic acid (3.7 g, 22.1 mmol). DIAD (4.6 mL, 22.1 mmol) was added dropwise via syringe over 1 h, keeping the temperature below 25° C. After 12 h, the reaction mixture was concentrated in vacuo and the residue was purified by flash silica gel chromatography (3:1 to 1:1 hexanes/EtOAc). The partially-purified product (42) was used without further purification. Mass spectrum, m/z [511.9] (M+H)+.

Provenance & Evidence