Nitro- and amino-substituted 10,10-dimethyl-10-sila-2-azaanthrones

Under conditions of the Mencke reaction, 10,10-dimethyl-9,10-dihydro-10-sila-2-azaanthracene is nitrated on the benzene fragment of the molecule, but the corresponding ketone is nitrated on the pyridine fragment. Dihydrosilaazaanthrone is nitrated by nitrating mixture in positions 5, 7, and 8 of the benzene fragment of the molecule. The nitro-substituted dihydrosilazaanthrones have been reduced to the corresponding amino derivatives. © 1986 Plenum Publishing Corporation

Nitro- and amino-substituted 10,10-dimethyl-10-sila-2-azaanthrones

Under conditions of the Mencke reaction, 10,10-dimethyl-9,10-dihydro-10-sila-2-azaanthracene is nitrated on the benzene fragment of the molecule, but the corresponding ketone is nitrated on the pyridine fragment. Dihydrosilaazaanthrone is nitrated by nitrating mixture in positions 5, 7, and 8 of the benzene fragment of the molecule. The nitro-substituted dihydrosilazaanthrones have been reduced to the corresponding amino derivatives. © 1986 Plenum Publishing Corporation

Preparation of pyridinium ylids, 1,4-dihydropyridines, and indolizines from γ-nitrophenyl- and γ-nitrobenzyl-pyridines

The transformations of N-phenacyl(p-nitrophenacyl, benzyl)-2,5-dimethyl-4-nitrophenyl (nitrobenzyl, benzyl)pyridinium bromides under the influence of potassium carbonate solution were studied. Stable pyridinium ylids were obtained in the case of γ-phenylpyridines that contain a nitro group in the benzene ring and in the case of γ-benzylpyridines with an N-nitrosubstituted phenacyl group. The conclusion that electron-acceptor substituents have a stabilizing effect on the stability of the ylids was confirmed. Under these conditions γ-nitrobenzyl derivatives are converted to substituted 1,4-dihydropyridines. The positions at which deprotonation of the starting quaternary pyridinium salts occurs and the formation of 1,4- and 1,2-dihydropyridines were established by PMR spectroscopy. The corresponding pyridinium salts were converted to a new group of indolizines containing a p-nitrophenyl (p-nitrobenzyl) substituent in the 2 or 7 position by the Chichibabin method. It was established that substituted dihydropyridines are converted to indolizines; ideas that confirm the scheme of the previously proposed mechanism for the formation of indolizines through a step involving ylids are expressed. © 1979 Plenum Publishing Corporation

Preparation of pyridinium ylids, 1,4-dihydropyridines, and indolizines from γ-nitrophenyl- and γ-nitrobenzyl-pyridines

The transformations of N-phenacyl(p-nitrophenacyl, benzyl)-2,5-dimethyl-4-nitrophenyl (nitrobenzyl, benzyl)pyridinium bromides under the influence of potassium carbonate solution were studied. Stable pyridinium ylids were obtained in the case of γ-phenylpyridines that contain a nitro group in the benzene ring and in the case of γ-benzylpyridines with an N-nitrosubstituted phenacyl group. The conclusion that electron-acceptor substituents have a stabilizing effect on the stability of the ylids was confirmed. Under these conditions γ-nitrobenzyl derivatives are converted to substituted 1,4-dihydropyridines. The positions at which deprotonation of the starting quaternary pyridinium salts occurs and the formation of 1,4- and 1,2-dihydropyridines were established by PMR spectroscopy. The corresponding pyridinium salts were converted to a new group of indolizines containing a p-nitrophenyl (p-nitrobenzyl) substituent in the 2 or 7 position by the Chichibabin method. It was established that substituted dihydropyridines are converted to indolizines; ideas that confirm the scheme of the previously proposed mechanism for the formation of indolizines through a step involving ylids are expressed. © 1979 Plenum Publishing Corporation