Synthesen von Heterocyclen, 35. Mitt.: �ber basische �ther von cyclischen Malonylverbindungen

in Wiley Online Library (wileyonlinelibrary.com).The synthesis of the 5-unsubstituted pyrido[3,2,1-jk]carbazol-6-one 4 can be achieved by the reaction of carbazole (1) and malonate derivatives, either in a three-step synthesis via 5-acetyl-pyridocarbazolone 3 or in a one-step reaction from 1 and malonic acid/phosphoryl chloride. The 5-acetyl derivative 5 can be transformed via a tosylate intermediate to 4-azido-pyridocarbazolone 11, which cyclizes by thermal decomposition to the isoxazolo-pyrido[3,2,1-jk]carbazolone 12. The thermolysis conditions were investigated by DSC. Nitration of pyridocarbazolone 4 and subsequent introduction of azide leads to azido derivative 23, which cyclizes on thermolysis to furazan-oxide derivative 24. Again, the thermolysis conditions were investigated by DSC. 5-Chloro-5-nitro-pyrido[3,2,1-jk]carbazole-4,6-dione, obtained from 4 by subsequent nitration and chlorination, forms by exchange of both 5-substituents 5,5-dihydroxy-pyridocarbazoledione 17, which acylates phenol to give 5-hydroxy-5-(p-hydroxyphenyl)-pyridocarbazoledione 20. Acid-catalyzed cyclodehydration of 20 forms a highly fused benzofuropyridocarbazole 21. Another C-C coupling at position 5 starts from 4-chloro-5-nitro-pyridocarbazolone 22 and diethyl malonate 2a, which forms the diethyl (nitrocarbazolyl)malonate 25. With dimethyl malonate 2c, the intermediate dimethyl (nitrocarbazolyl)malonate gives on thermolysis the (nitrocarbazolyl)acetate 27 by loss of one ester group.

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Synthesis and reactions of 4‐hydroxy‐8,9,10,11‐ tetrahydropyrido[3,2,1‐jk]carbazol‐6‐ones

Stadlbauer¹,

Dang²,

Berger³

2010

Journal of Heterocyclic Chem

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in Wiley InterScience (www.interscience.wiley.com).Tetrahydrocarbazoles 4 obtained from phenylhydrazines and cyclohexanones gave by cyclocondensation with 2-substituted malonates 5 in all cases 4-hydroxy-8,9,10,11-tetrahydropyrido[3,2,1-jk]carbazol-6-ones 6 by attack at the nitrogen and the aromatic ring of tetrahydrocarbazoles 4; the direction of the cyclization was not dependent on substituents either in the aromatic or the saturated ring; isomeric pyridocarbazoles could not be isolated. Electrophilic substitutions of pyridocarbazoles 6 under mild conditions took place exclusively at the 5-position and gave pyridocarbazolediones 9-11 with 5nitro-, 5-hydroxy or 5-chloro-substituents. Exchange of the chloro substituent in 11 gave 5-azido-and 5-amino products 12, 14 or 16. Reactions at the aromatic ring were not observed. Chlorination of 4hydroxypyridocarbazoles 6 with phosphoryl chloride by nucleophilic substitution took place exclusively at the 4-position and gave 4-chloropyridocarbazolones 17, which were further reacted to azides and amines 18, 19.

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Synthesen von Heterocyclen, 35. Mitt.: �ber basische �ther von cyclischen Malonylverbindungen

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Benzacridines and Condensed Acridines

Benzacridines and Condensed Acridines

5‐Unsubstituted Pyrido[3,2,1‐jk]carbazol‐6‐ones: Syntheses, Substitution, and Cyclization Reactions

Synthesis and reactions of 4‐hydroxy‐8,9,10,11‐ tetrahydropyrido[3,2,1‐jk]carbazol‐6‐ones

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