IR spectra of selenophenopyrylium salts

On the basis of the IR spectra of 16 alkyl-substituted selenopheno[2,3-c]- and selenopheno-[3,2-c]pyrylium salts and a model calculation of the frequencies and the forms of their normal vibrations, an assignment of the frequencies of the skeletal vibrations of the heterocycles is put forward.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1495–1497, November, 1973.     

Reaction of acridinium salts with phenylhydrazones and phenylhydrazides

4-(9-Acridinyl)phenylhydrazones and phenylhydrazides were obtained by condensation of the phenylhydrazones of aromatic aldehydes and ketones and the phenyl-hydrazides of carboxylic acids with acridinium salts in the presence of an oxidizing agent.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 387–391, March, 1975.     

Nucleophilic substitution of hydrogen (9-H) in acridinium salts by phenols

Under oxidative conditions, quaternary and protic acridinium salts undergo substitution of the hydrogen atom in the 9 position by a phenol residue to give 9-hydroxyarylacridines. The latter may be formed under the same conditions from complexes of acridine hydrochloride with phenols obtained by an independent method.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 266–271, February, 1976.     

Electronic absorption spectra of pyrylium and benzodihydrochromenylium salts

The electronic absorption spectra of benzodihydrochromenylium, tetrahydrochromenylium, and dichloropyrylium salts were studied for the first time. It was noticed that intramolecular charge transfer takes place mainly between the substituent at position 4 of the pyrylium ring and the π-system of the cation as a whole, while the bathochromic shift depends substantially on the geometry of the molecule. It was shown that the chlorine atoms have an effect on the form of the spectra when they are introduced into the ring of the pyrylium cation and into the aryl substituents. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1152–1159, August, 2008.     

Photodissociation of hydrogen halide molecules on free ice nanoparticles

Photodissociation of water clusters doped with HX(X=Br,Cl), molecules has been studied in a molecular beam experiment. The HX(H2O)n clusters are dissociated with 193 nm laser pulses, and the H fragments are ionized at 243.07 nm and their time-of-flight distributions are measured. Experiments with deuterated species DBr(H2O)n and HBr(D2O)n suggest that the photodissociation signal originates from the presence of the HX molecule on the water cluster, but does not come directly from a photolysis of the HX molecule. The H fragment is proposed to originate from the hydronium molecule H3O. Possible mechanisms of the H3O production are discussed. Experimental evidence suggests that acidic dissociation takes place in the cluster, but the H3O+ ion remains rather immobile.     

The structures of the hydrogen halide salts of succinonitrile and related compounds

The constitutions of the hydrogen halide salts of succinonitrile are shown to be 2-amino-5,5-dihalo-1-pyrrolinium halides (II) and are thus the next lower homologs of the corresponding salts of glutaronitrile.¹ On the other hand the homologous 2,3-diphenyl-succinonitrile when treated with hydrogen bromide leads to 5-amino-2-bromo-3,4-diphenyl-3 -pyrrole hydrobromide (IX) which is tautomerically different from the analogous salt obtained previously from 2,5-diphenylglutaronitrile. The hydrolysis of IX has been examined and the products completely characterized. 2,2,3,3-Tetramethylsuccinonitrile in ether affords 5-imino-3,3,4,4-tetramethyl-2-pyrrolidone hydrobromide when treated with anhydrous hydrogen bromide whereas 1,1′-dicyano-1,1′-bicyclohexyl is unreactive towards this gas, in aprotic solvents.     

IR absorption spectra of 1-aryl-3-pyrazolidones

An examination of the frequencies and intensities of the valence vibration bands of carbonyl groups established that the phenyl group interacts with the C=O group of 1-phenyl-3-pyrazolidone and its m- and p-tolyl derivatives in solution. It is assumed that the interaction is accomplished through the N₁ and N₂ atoms in the sp² state. 1-Phenylpyrazolidone derivatives are strongly associated in CC1₄ and CHCl₃ solutions. The association decreases on passing from CCl₄ to CHCl₃ solutions and when there are methyl groups in the ortho positions of the phenyl rings. The energy of association between the 1-phenylpyrazolidones and organic bases (acetonitrile, ethyl acetate, and dioxane), evaluated from the shift in _nh, is 1.36–3.5 kcal/mole. The frequencies and integral intensities of the bands of the C=O and NH groups in chloroform were measured.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1678–1682, December, 1970.