Regioselective sulfonation of 2-porphyrinylthiophene under kinetic and thermodynamic control

✍ Scribed by Yonbon Arai; Jotaro Nakazaki; Hiroshi Segawa

• Book ID: 104095666
• Publisher: Elsevier Science
• Year: 2008
• Tongue: French
• Weight: 230 KB
• Volume: 49
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/j.tetlet.2008.07.124

✦ Synopsis

Sulfonation of meso-tetra(thien-2 0 -yl)porphyrin with concentrated sulfuric acid was found to produce several tetrasulfonated meso-tetra(thien-2 0 -yl)porphyrin isomers, where sulfonic acid groups were substituted at the 5-or the 4-positions of the thienyl groups, and the tetrasodium salts of the isomers were successfully isolated by reversed-phase HPLC. Temperature dependence of the production ratio of the isomers revealed that sulfonation reactions at the 5-and the 4-positions of 2-porphyrinylthiophene occur under kinetic and thermodynamic control, respectively.