2-Benzopyrylium salts. 27. Formation of substituted chrysenes from 1-methyl-2-benzopyrylium salts

1-Methyl-2-benzopyrylium salts with a free position of the heteroring primarily form substituted chrysenes. In alkaline media this process does not proceed through the intermediate formation of 1,5-diketones.For Communication 26, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1472–1476, November, 1984.     

Synthesis and structures of ethoxymethylene derivatives of 1,3-diethoxycyclohexenylium perchlorate

1,3-Diethoxy-4,6-di(ethoxymethylene)-5,5-dimethylcyclohexenylium perchlorate (6a) was synthesized from 1,3-diethoxy-5,5-dimethylcyclohexenylium perchlorate by successive introduction of ethoxymethylene groups. Perchlorate6a was also obtained from dimedone in one preparative step. Compound6a was studied by X-ray diffraction analysis. The bond lengths in the fragment containing the C(1)–C(4) and C(6) atoms of the six-membered ring of the cation are substantially equalized and close to the C_arom-C_arom bond length. Apparently, this fact indicates that the positive charge is primarily delocalized over the aromatic system. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2300–2304, November, 1998.     

2-Benzopyrylium salts. 26. Recyclization of 2-benzopyrylium salts to α-naphthols

The behavior of 2-benzopyrylium salts with a CH₂ group in the 1 position at pH 7 was studied, and it was established that they undergo recyclization to -naphthols under these conditions. A mechanism for the conversion is proposed. One of the intermediates, viz., 3-hydroxy-1-tetralone, was isolated.See [1] for communication 25.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1184–1187, September, 1982.     

Entanglement Swapping in the Presence of White and Color Noise

The influence of white and color noise on the outcome of the entanglement swapping process is investigated in a four-qubit system. Critical degree of noise in initial state, that could destroy entanglement in a result state is presented. The entanglement characteristics, such as concurrence, tangle, etc. are compared. Results could be helpful for experiments regarding entanglement swapping as conditions for initial quantum entangled states, to obtain entangled result state.     

2-Benzopyrilium salts. 28. Conversion of 1-methyl-2-benzopyrilium salts into substitute chrysenes in basic media

It is shown that the conversion of 1-methyl-2-benzopyrilium salts into chrysenes in basic media occurs via an intermediate dimeric pseudobase. The properties of this have been examined, and mechanisms are proposed for its formation and conversion into chrysenes.For No. 27, see [1].Translated from Khimiya Geterotsiklichesklkh Soedinenii, No. 7, pp. 910–914, July, 1985.     

2-benzopyrylium salts. 33. 4-1′-Dimerization of 2-benzopyrylium salts. Formation of benz [a] anthracenes

The conversion of 2-benzopyrylium salts to benz [a] anthracenes, which proceeds through prior dimerization of a new type, was observed. An intermediate dimer was isolated, its properties were studied, and assumptions regarding the mechanisms of its formation and conversion to benz [a] anthracenes, cenes were expressed.See [1] for Communication 32.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1185–1189, September, 1988.     

Molecular Polarizability of Organic Compounds and Their Complexes: XLVII. Conformations of Some 2,4,6-Triarylpyridines, 2-Aryl-4-phenyl-6-tert-butylpyridines,and the Corresponding Pyridinium Cations in Solutions,as Determined from the Cotton-Mouton Effect

The conformations of some 2,4,6-triarylpyridines, 2-aryl-4-phenyl-6-tert-butylpyridines, and the corresponding pyridinium cations in dioxane and acetonitrile solutions were determined from the Cotton-Mouton effect. These systems are nonplanar; the angles by which the aryl substituents at positions 2 and 6 of the heteroring are turned relative to the heteroring plane are close to those observed in biphenyl and its p-substituted derivatives; these angles depend on substituents in the rings and, in the case of cations, at the pyridinium nitrogen atom.     

Acetals and Vinyl Ethers of Unsaturated Aldehydes and Ketones in the New Syntheses of Heterocyclic Compounds: XII. New Alternatives of Acid Condensation of Cyclohexane-1,4-diones with Hydroxyarylaldehydes under Dehydration Conditions. Fluorecence Spectra of the Products

1,3-Diethoxy-2-R-5,5-R',R'-1-cyclohexenylium perchlorates in condensation with 2-hydroxyarylaldehydes under dehydration conditions give rise to 3-ethoxy-1,2-dihydroxanthylium perchlorates that with the second molecule of 2-hydroxyarylaldehyde afford 13H-chromeno[3,2-b]xanth-5-ylium perchlorates, and with primary and secondary amines yield 3-(R²,R³-amino)-1,2-dihydroxanthylium perchlorates. The condensation of 2-bromodimedone with salicylaldehydes in triethyl orthoformate and perchloric acid medium furnished 6-bromo-13,13-dimethyl-13H-chromeno[3,2-b]xanth-5-ylium perchlorates. The latter compounds show strong fluorescence in 530-630 nm region with 0.48-0.98 quantum efficiency. Under similar conditions the dimedone and 2-acetyldimedone afford with 2-hydroxyarylaldehydes tris-condensation products: 2,10-dimethoxy-6-(3-methoxy-6-oxo-2,4-cyclohexadienylidenemethyl)-7,7-dimethyl-7H-chromeno[2,3-a]-xanth-13-ylium perchlorate and 2,10-dimethoxy-6-(6-methoxychromylium-2-yl)-13,13-dimethyl-13H-chromeno[3,2-b]xanth-5-ylium diperchlorate respectively.