Te. Clement et al., SYNTHESES AND STRUCTURAL-PROPERTIES OF SEVERELY DISTORTED PORPHYRINS - N-METHYL DERIVATIVES, Heterocycles, 45(4), 1997, pp. 651-658
Syntheses and characterization of a series of N-methylated derivatives
of sterically distorted porphyrins are reported; the work includes th
e first example of a tetra-N-methylated porphyrin obtained by methylat
ion of an intact porphyrin.