Acetic Acid → HCID 2801523, compound

Participants

Reaction Conditions

Reaction Steps

Diethyl oxalate (83 ml, 0.61 mol) was added dropwise to a stirred solution of diethyl 2,2′4-(4-methoxyphenyl)azanediyl)diacetate (4) (180 g, 0.61 mol) in NaOEt (21% by wt in EtOH) (506 ml, 1.3 mol), the mixture was stirred at 100° C. for 1 h. The reaction was quenched with acetic acid (210 ml, 3.7 mol) and the resulting suspension was poured into iced water (1 L), the resulting off-white solid collected by vacuum filtration. The crude product was recrystallised from hot EtOH (3.5 L) to give diethyl 3,4-dihydroxy-1-(4-methoxyphenyl)-1H-pyrrole-2,5-dicarboxylate (UL2-001) (152 g, 71%) as a white solid: m/z 350 (M+H)+ (ES+); 348 (M−H)− (ES−). 1H NMR (400 MHz, DMSO-d6) δ 8.64 (s, 2H), 7.13-7.01 (m, 2H), 6.92-6.81 (m, 2H), 3.99 (q, J=7.1 Hz, 4H), 3.78 (s, 3H), 0.99 (t, J=7.1 Hz, 6H).

Provenance & Evidence