Phenol → 3-Phenoxy-hexahydro-pyrrolo[3,2-b]pyrrole-1,4-dicarboxylic acid 4-benzyl ester 1-tert-butyl ester

Participants

Reaction Steps

To a solution of 11 (600 mg, 1.65 mmol) in THF (10 mL) was added phenol (186 mg, 1.98 mmol) and Ph3P (520 mg, 1.98 mmol). DIAD (459 mg, 2.31 mmol) was then added and the reaction mixture was immersed into a preheated (75° C.) oil bath. After 16 h, the reaction mixture was concentrated in vacuo and the residue was passed through a short column of silica gel (4:1 hexanes/EtOAc). The crude product was then purified by reverse-phase HPLC (2″ Dynamax® C18, 10-70% ACN/water containing 0.1% HOAc over 30 min; Flow: 40 mL/min) to afford 340 mg (46%) of 12 as a white solid. 1H NMR (CDCl3, 300 MHz), mixture of rotomers: δ7.37-7.27 (m, 6H), 7.22 (m, 1H), 7.04 (m, 1H), 6.96-6.88 (m, 1H), 6.81 (d, J=8.4 Hz, 1H), 5.27-5.13 (m, 2H), 5.01 (dd, J=3.3, 6.3 Hz, 0.5H), 4.77 (d, J=2.7 Hz, 0.5H), 4.57-4.45 (m, 1H), 4.43-4.32 (m, 1H), 3.99-3.89 (m, 1H), 3.85-3.73 (m, 1H), 3.37 (m, 1H), 3.21 (dt, J=5.7, 11.7 Hz, 1H), 2.38 (m, 0.5H), 2.23 (dd, J=5.7, 13.2 Hz, 0.5H), 1.91-1.83 (m, 1H), 1.47 (m, 9H) ppm. Mass spectrum, m/z [339.2] (M−Boc)+.

Provenance & Evidence