Pyrrole → HCID 136204851, compound

Participants

Reaction Steps

To a refluxing solution of propionic acid (200 mL) and 1-methylpyrazole-4-carboxaldehyde (48, 0.92 g, 8.32 mmol), prepared according to literature procedure (Finar, I. L.; Lord, G. H. J. Chem. Soc. 1957, 3314-3315), was added pyrrole (0.63 mL, 8.32 mmol). The reaction was covered with foil and was heated under reflux for 3.5 h. Upon cooling the reaction mixture was exposed to air overnight. The propionic acid was then removed by vacuum distillation. The crude residue was dissolved in 5% MeOH/CH2Cl2, then adsorbed onto silica gel (5.3 g). Purification by column chromatography (5% MeOH/CH2Cl2) provided porphyrin 49 as a purple solid (231 mg, 17.5%): 1H NMR (300 MHz, DMSO-d6) δ −2.74 (s, 2 H), 4.28 (s, 12 H), 8.31 (s, 4 H), 8.67 (s, 4 H), 9.16 (s, 8 H).

Provenance & Evidence