From porphyrin benzylphosphoramidate conjugates to the catalytic hydrogenation of 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin.
Three new porphyrin aminoalkyl dibenzylphosphoramidates were synthesized by nucleophilic aromatic substitution of one p-fluorine atom of 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin (TPPF 20 ) by primary aminoalkyl dibenzylphosphoramidates. The nucleophilic aromatic substitution was promoted by microwave irradiation in N-methyl-2-pyrrolidinone. Attempts to remove the benzyl groups of the phosphoramidate moiety by hydrogenolysis with 10% Pd/C led to the cleavage of the P-N bond and the reduction of the macrocycle to hydroporphyrin-type derivatives. The extent of the effect of the catalytic hydrogenation to TPPF 20 with 10% Pd/C was then studied with a variety of solvents. The results showed that ethanol/DMF is the solvent of choice to produce chlorin TPCF 20 and an ethanol/DMF/NEt3 mixture is more adequate to produce isobacteriochlorin (TPIF 20 ).
Departamento de Química Orgânica, Universidade Federal Fluminense, 24020-141 Niterói, RJ, Brasil, ; Department of Chemistry & QOPNA, University of Aveiro, 3810-193 Aveiro, Portugal.
Marcos C
MC
de Souza
Departamento de Química Orgânica, Universidade Federal Fluminense, 24020-141 Niterói, RJ, Brasil.
Leandro F
LF
Pedrosa
Departamento de Química Orgânica, Universidade Federal Fluminense, 24020-141 Niterói, RJ, Brasil.
Géssica S
GS
Cazagrande
Departamento de Química Orgânica, Universidade Federal Fluminense, 24020-141 Niterói, RJ, Brasil.
Vitor F
VF
Ferreira
Department of Chemistry & QOPNA, University of Aveiro, 3810-193 Aveiro, Portugal.
Maria G P M S
MG
Neves
Department of Chemistry & QOPNA, University of Aveiro, 3810-193 Aveiro, Portugal.
José A S
JA
Cavaleiro
catalytic hydrogenation; chlorin; isobacteriochlorin; phosphoramidate; porphyrin