Benzylation of 2,5-dimethyl-4-phenyl(p-alkylbenzyl) pyridines

New substituted 4-phenyl-2-benzyl- and 2,4-dibenzylpyridines were obtained, and some of their transformations were studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 91–94, January, 1972.     

Hydrogenation of 2,5-dimethyl-4-phenyl(p-alkylbenzyl) pyridines over metal sulfides

The corresponding substituted piperidines were obtained in yields from 40 to 99.5% by the hydrogenation of 2,5-dimethyl-4-phenylpyridine and 2,5-dimethyl-4-[p-methyl(p-ethyl)benzyl]pyridines in the presence of rhenium, platinum, and palladium sulfides.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 88–90, January, 1972.     

2,5-Dimethyl-4-(p-aminobenzyl)pyridine in the synthesis of substituted quinolines,pyridoindazoles, and isoquinolinoquinolines

2,5-Dimethyl-4-pyridyl(6-quinolyl)methane was obtained from 2,5-dimethyl-4-(p-aminobenzyl)pyridine via the Skraup reaction. The product was nitrated to 2,5-dimethyl-4-pyridyl (5-nitro-6-quinolyl)methane, which was reduced to 2,5-dimethyl-4-pyridyl (5-amino-6-quinolyl)methane. It was established that the diazo compound formed from this amino derivative is converted to 1H,3-(2,5-dimethyl-4-pyridyl)-pyrido [2,3-g]indazole as a result of intramolecular cyclization. 9-Methyliso-quinolino [7,6-f]quinoline was obtained by catalytic dehydrocyclization of 2,5-dimethyl-4-pyridyl (6-quinolyl)methane. 2,5-Dimethyl-4-pyridyl(5-nitro-6-quinolyl)methane has chemochromic properties.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 677–680, May, 1980.     

Synthesis of 2-(4-cyanophenyl)-5-(4-n-alkyl- and alkoxyphenyl) pyridines

New liquid-crystalline 2-(4-cyanophenyl)-5-(4-alkyl- and alkoxyphenyl)pyridines were obtained by condensation of 1-dimethylamino-3-dimethylimmonia-2-(4-alkyl- or alkoxyphenyl)-1-propene perchlorates with 4-cyanoacetophenone and subsequent conversion of the 1-dimethylamino-2-(p-alkyl- or alkoxyphenyl)-4-(p-cyanobenzoyl)-1,3-butadienes to 5-(4-alkyl- or alkoxyphenyl)-2-(4-cyanophenyl)pyrylium perchlorates and refluxing of the latter with ammonium acetate in acetic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1392–1394, October, 1985.     

The Synthesis of 2-Amino-4-(4-imidazolyl)pyridines

A general synthetic scheme for the preparation of 2-amino-4,(4-imidazolyl)pyridines, potential histamine H₂ antagonists, is described. The synthesis is based on the Neber rearrangement of l,(4-pyridyl)l-alkanone oxime 0-tosylates to the appropriate α-aminoketones or α-aminoketals, which are then converted to the corresponding imidazoles. The reaction of Grignard reagents with 2-chloroisonicotinonitrile, as well as nucleophilic displacement of chloride by amines on 2-chloroisonicotinonitrile and derivatives, are discussed in relation to the preparation of the ketone intermediates.     

Regiospecific synthesis of 4-(2-oxoalkyl)pyridines

[reaction: see text]. A new and operationally simple method has been developed for the regiospecific syntheses of 4-(2-oxoalkyl)pyridines from ketones and pyridine in good yields, using triflic anhydride to activate the pyridine ring.     

2,5-Dimethyl-4-phenyl- and 3,6-dimethyl-2,4-diphenylpiperidines

2,5-Dimethyl-4-phenylpiperidine and 3,6-dimethyl-2,4-diphenylpiperidine were obtained by reduction of the corresponding substituted pyridines. Several of their transformations are examined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1356–1358, October, 1970.     

(4R)-5,5-二甲基-4-苄硫甲基-2-噁唑烷酮的合成

以价廉易得的天然L-半胱氨酸为原料,经巯基保护、酯化、氨基保护、格氏反应及环化等5步反应,合成了一个新的手性助剂(4R)-5,5-二甲基-4-苄硫甲基-2-噁唑烷酮,总收率31%.产物结构经IR,~1H NMR,~(13)C NMR及MS表征.     

Polymesomorphism in a homologous series of 2-(4-alkoxyphenyl)-5-(4-methylphenyl)pyridines

A new series of 2-(4- n -alkoxyphenyl)-5-(4-methylphenyl)pyridines (CH C H C H NC HOC H , n 1-10) (APMPP), which are teraryl compounds containing a pyridine ring in n 2 m 1 the centre position of the rigid core, was synthesized and the phase transitions of the homologues were studied using DSC measurements, polarizing optical microscopy and miscibility tests with terephthalylidene-bis-4- n -pentylaniline (TBPA). Only a nematic phase was found for the shorter alkoxy homologues with n 4. The longer alkoxy homologues with n 4 showed the sequence of enantiotropic phase transitions CrG-SmF-SmC-SmA-N-I, while a monotropic CrH phase was observed for the n 5-10 homologues. Interestingly, the polymesomorphisms appear when n is larger than 4. 3 6 4 5 3 6 4     

3-(4-Hydroxyphenylthio)pyrrolidine-2,5-diones

3-(4-Hydroxyphenylthio)pyrrolidine-2,5-diones were prepared by the conjugate addition of substituted 4-hydroxybenzenethiols to 1-alkyl-1H-pyrrole-2,5-diones. The analytical and spectral data are reported.     

1,1-Dimethyl-1-(trialkoxysilylmethyl)hydrazinium and 1,1-Dimethyl-1-(silatranylmethyl)hydrazinium Halides

Formerly unknown 1,1-dimethyl-1-(trialkoxysilylmethyl)- and 1,1-dimethyl-1-(silatranylmethyl)hydrazinium halides were prepared by reaction of 1,1-dimethylhydrazine with (halomethyl)trialkoxysilanes XCH₂Si(OR)₃ (X = Cl, I; R=Me, Et) and 1-(halomethyl)silatranes XCH₂Si(OCH₂CH₂)₃N (X = Cl, Br). 1,1-Dimethyl-1-(silatranylmethyl)hydrazinium chloride and iodide were also obtained by transetherification of corresponding 1,1-dimethyl-1-(trimethoxysilylmethyl)hydrazinium halides with tris(2-hydroxyethyl)amine.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 6, 2005, pp. 915–919.Original Russian Text Copyright © 2005 by Sorokin, Voronkov.     

4-alkyl(aryl)-1-germacyclohexa-2,5-diene

enThe 1(Z),4(Z)-1,5-dilithium-3R-3-methoxypenta-1,4-dienes react with diaryldichlorogermanes and dialkyldichlorogermanes to give the 1,1-diaryl- and 1,1-dialkyl-4R-4-methoxy-1-germacyclohexa-2,5-dienes, respectively.With phenyltrichlorogermane, methyl- and ethyl-trichlorogermanes the E/Z-isomeric 1-phenyl(methyl,ethyl)-1-chloro-4R-4-methoxy-1-germacyclohexa-1,3-dienes are obtained, reduction of these with LiAlH₄ makes the corresponding 1-aryl-(alkyl)-1H-4R-4-methoxy-1-germacyclohexa-2,5-dienes available.Reduction of 1-ethyl-1-chloro-4-phenyl-4-methoxy-1-germacyclohexa-2,5-diene with LiAlH₄ yields by additional ether cleavage 1-ethyl-1H-4-phenyl-1-germacyclohexa-2,4-diene.The ¹H NMR (60 MHz, 90 MHz), ¹³C NMR, IR and mass spectra are discussed, several ¹H NMR spectra are calculated according to the LAOCOONLAME program.