Potassium Carbonate → HCID 89610318, compound

Participants

Reaction Steps

tert-Butyl 2-bromoacetate (0.55 ml, 3.41 mmol) was added dropwise to a stirred solution of diethyl 3-(benzyloxy)-4-hydroxy-1-(4-methoxyphenyl)-1H-pyrrole-2,5-dicarboxylate (23) (1.0 g, 2.28 mmol) and K2CO3 (0.63 g, 4.55 mmol) in DMF (20 mL). The reaction mixture was stirred at RT for 18 h, and partitioned between EtOAc (200 mL) and sat. NaHCO3 (aq.) (200 mL), the organic layer was separated and washed with sat. NaHCO3 (aq.) (2×200 mL), dried (MgSO4), filtered and solvents removed in vacuo to give a yellow oil. The residue was purified by silica gel chromatography (120 g, 0-20% EtOAc in isohexane) to afford diethyl 3-(benzyloxy)-4-(2-(tert-butoxy)-2-oxoethoxy)-1-(4-methoxyphenyl)-1H-pyrrole-2,5-dicarboxylate (UL2-028) (912 mg, 72%) as a pale yellow oil: m/z 554 (M+H)+ (ES+). 1H NMR (400 MHz, DMSO-d6) δ: 7.49-7.44 (m, 2H), 7.43-7.31 (m, 3H), 7.15-7.08 (m, 2H), 6.94-6.88 (m, 2H), 5.12 (s, 2H), 4.59 (s, 2H), 4.02-3.94 (m, 4H), 3.79 (s, 3H), 1.40 (s, 9H), 1.02 (t, J=7.1 Hz, 3H), 0.97 (t, J=7.1 Hz, 3H).

Provenance & Evidence