The influence of nitrate salts and complex metal ion to regio-selective synthesis of 2-nitro-5, 10, 15, 20-tetra-(4-Methoxyphenyl) prophyrinato metal

A series of 2-nitro-5, 10, 15, 20-tetra (4-methoxyphenyl) porphyrinato metals were regioselectively synthesized with nitrate salts as nitrating reagent in acetic acid/acetic anhydride for preparation of 2-substituted porphyrin. The influence of nitrate salts and complex metal ion to the reaction were investigated. The extent of 2-nitration increased with the electronegativity of the central metal. When Cu(NO₃)₂×3H₂O was used as nitrating reagent, almost quantitative yields of 2-nitro porphyrin were obtained in the case of Cu (II) or Ni (II) chelates, while Zn(II) or Mn(II) chelates gave 50% and 30% yields respectively. If Zn(NO₃)₂×10H₂O was used as nitrating agent, no product was found for Cu(II) or Ni(II) chelates, 12% was found for Zn(II) chelates. The other metal ion and nitrate salts were also found in quite different influence. Foundation item: Supported by the National Natural Science Foundation of China (29872033) Biography: Chen Zhang-ping (1946-), male, Professor, research direction, porphyrin.