Amination of 4-hydroxypyridocarbazolones 1 with aniline or benzylamine gave in good yields 4-amines 3; with piperidine in a sealed tube from 4-hydroxy- or 4-chloro-5-alkylpyridocarbazolones 1 or 4 ring opened 1-acylcarbazoles 5 were obtained. Only 4-hydroxy-5-phenyl-pyridocarbazolone 1d gave 4-amines 6. Reduction of 4-azidopyridocarbazolones 7 either by catalytic hydrogenation or in a 2-step synthesis via phosphazenes 8 gave 4-aminopyridocarbazolones 9. Amines 9 were also obtained from benzylamines 3 by catalytic debenzylation. A one step amination of 4-hydroxy-5-phenylpyridocarbazolone 1d via debenzylation to 9d was observed by reaction with benzylammonium chloride. At elevated temperatures the highly fused 6,13b-diaza-indeno[1,2,3-hi]chrysenone 10 was formed from 1d.
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