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Amination par NH 3 liquide des chloro-2 nitro-5- et chloro-2 dinitro-3,5 pyridines en presence d'amidure ou de permanganate de potassium; orientation des reactions, mecanismes

Cadmium tetrabenzoporphyrin, tetrabenzoporphyrin, and the bispyridine complex of magnesium tetrabenzoporphyrin were synthesized. As judged from the visible absorption spectra these compounds are not contaminated with porphyrin-like impurities. 100-MHz 1H Fourier-transform n.m.r. spectra of the above mentioned compounds are presented. From the low-temperature e.s.r. spectra it can be concluded that the lowest triplet state of biligated magnesium tetrabenzoporphyrin exhibits a static Jahn–Teller distortion resulting in a loss of four-fold molecular symmetry.

The hitherto unknown u.v. induced amination of 4-X-6-phenylpyrimidines (V; X = Cl, Br, or I) to give 4-amino-6-phenylpyrimidine (VI), using liquid ammonia as solvent and reactant, is described. The reactivity order is found to be I > Br > Cl. Evidence is presented that the photoamination does not occur according to an SN(ANRORC) or an SN(AE) mechanism. Since an inhibitory effect of the radical scavenger di-t-butyl nitroxide is observed in the photoamination, a reaction pathway involving a radical as intermediate is postulated.