A. Abeysekera, R. Grigg, J. Trocha‐Grimshaw
1980
Citations
0
Influential Citations
9
Citations
Journal
Tetrahedron
Abstract
Abstract Improved procedures are reported for the preparation of mono-, di- and tri-N-methyl-etioporphyrin I. Demethylation of N a , N b , N c -trimethyletioporphyrin I under acidic, basic or thermal conditions gives N a , N b -dimethyl etioporphyrin I. N-Methylation of octaalkyl-5-azaporphyrins leads, in general, to mixtures of the isomeric mono-, di- and tri-N-alkylated 5-azaporphyrins. An X-ray crystal structure of N a ,N b -dimethyl etioporphyrin I triiodide confirms the trans arrangement of the N-Me groups. The two N-methylated pyrrole rings are twisted 27° to each other.