Synthesis and properties of 2-alkyl-5-ethynyltetrazoles

2-Alkyl-5-ethynyltetrazoles were synthesized. It is shown that ethynyltetrazoles have a triple bond with increased electrophilicity. They readily add aliphatic alcohols and amines and undergo aminomethylation, the Iotsich reaction, oxidative dimerization, and the cycloaddition of azides. 1-Phenyl-3-tetrazolyl-2-propyne, which has the properties of α-acetylenic ketones, was obtained by selective oxidation of tetrazolylethynylcarbinol. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 842–847, June, 1980.     

Synthesis and spectral properties of 3-furyl-4-hydroxycoumarins

3-(5-Ethoxycarbonyl-2-furyl)-4-hydroxy-6-R-7-methoxycoumarins and their 4-acyl derivatives have been synthesized. Their¹H and¹³C NMR and IR spectra, and also their absorption and fluorescence spectra, have been studied. It has been shown that some of the substances synthesized can be used as fluorescent probes in the study of membranes and of protein preparations.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 45–51, January–February, 1998.     

Synthesis of 4-methyl-5-alkyl-2-imidazolinones

Conclusions 4-Methyl-5-alkyl-2-imidazolinones were synthesized by heating 3-halo-2-alkanones with a mixture of piperidine, N,N-diethylacetamide, urea, zinc chloride and magnesium carbonate.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1887–1890, August, 1987.     

Synthesis of photoactive 5-aroyl-4-furyl-2-(morpholin-4-yl)thiazoles

5-Aroyl-4-furyl-2-(morpholin-4-yl)thiazoles were synthesized by the reaction of (morpholin-4-ylthiocarbonyl)furan-2-carboxamide with α-bromoketones.     

Synthesis of some 2-alkyl-4-quinolone and 2-alkyl-4-methoxyquinoline alkaloids

Acid-catalyzed condensation of a series of 3-oxoalkanoic acid esters with aniline affords the corresponding 2-alkyl-4-quinolones in good yield. Treatment of these compounds with methyl iodide affords 2-alkyl-4-methoxyquinolines and 2-alkyl-N-methylquinolones. Three of the compounds are naturally-occurring alkaloids which are synthesized here for the first time.     

Synthesis and photochromic properties of 5-acetyl-substituted indolinospirochromenes

Four photochromic 5-acetyl-substituted indolinospirochromenes were synthesized. The introduction of an acetyl group does not change the spectral characteristics of the merocyanine form but leads to a decrease in the efficiency of photocoloring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1654–1658, December, 1979Original article submitted January 9, 1979.     

The Synthesis of 2-Alkylthio-3-alkyl-5-arylmethylidene4H-imidazol-4-ones

2-alkylthio-3-alkyl-5-arylmethylidene-4H-imidazol-4-ones were synthesized by the S-alkylation and N-alkylation of 2-thioxo-5-arylmethylidene-4-imidazolidinones, which were obtained via a tandem aza-Wittig reaction of vinyliminophosphoranes, carbon disulfide, and excess ammonium hydroxide (28% NH₃ in water).     

Synthesis and metal-ion binding properties of new N2S4- and N2S5-donor macrocycles

Synthetic procedures for new N₂S₄- and N₂S₅-donor macrocycles (2 and 4) were given. The ligands were prepared by the reaction of NaBH₄ with the appropriate macrocyclic diamide in the presence of boron trifluoride ethyl etherate in dry tetrahydrofuran (THF). Solvent extraction method was used to evaluate metal-ion binding properties of the new ligands. The solvent extraction experiments suggested that the reduced macrocycles have Ag⁺ and Hg²⁺ selectivities compared to Pb²⁺, Co²⁺, Zn²⁺, Ni²⁺, Cu²⁺, Mn²⁺ and Cd²⁺ ions. The extraction constants (log K _ex) and complex compositions were determined for Ag⁺ and Hg²⁺ complex of compound (4).     

Furylcyclohexenones. 1. Synthesis and properties of 3- and 5-furyl-6-ethoxycarbonylcyclohexenones

3- and 5-Furylcyclohexenones were obtained by the Michael reaction of furan chalcones with acetoacetic ester. Intermediate -cycloketols were isolated in many cases. It was found that transformations of -cycloketols by HClO₄ and TrClO₄ were a function of the nature of the substituent in position5 of the alicycle. 5-Arylketols undergo dehydration, while 5-furyl derivatives split both water and the furan fragment, resulting in aromatization of the alicycle. The structure of the synthesized compounds was confirmed by the IR and PMR spectra.Kuban State Technological University, Krasnodar 350072. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 639–647, May, 1996. Original article submitted February 21, 1996.     

Synthesis of 1-alkyl-2-nitroimidazole-5-carboxaldehydes

We report the preparation of 1-methyl- and 1-ethyl-2-nitroimidazole-5-carboxaldehydes (Ia,b). For Ia three different routes of synthesis are described, which appear of general value for preparing 1-alkyl substituted 2-nitroimidazole-5-carboxaldehydes.     

Synthesis and some properties of 4-alkyl-5-cyano-6-mercapto-3,4-dihydropyridin-2(1H)-ones

Condensation of propionic (or acetic) aldehyde, cyanothioacetamide, Meldrum's acid, andN-methylmorpholine occursvia the intermediate formation of the corresponding Michael adducts and yields 4-alkyl-5-cyano-6-mercapto-3,4-dihydropyridin-2(1H)-ones. The oxidation of the reaction products with DMSO and their alkylation were studied. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2016–2019, November, 1997.     

Synthesis and mesomorphic properties of aryl 5-alkyl-(and alkoxy) pyrimidine-2-carboxylates

Some aryl 5-alkyl(and alkoxy)pyrimidine-2-carboxylates (I) and 5-alkylpyrimidinoyloxybenzoates (II) have been obtained. It has been found the former do not display mesomorphism, but the latter are nematic liquid crystals with a range over which the mesophase exists of 50–90C. The transition to the liquid crystal state in these compounds takes place at approximately the same temperatures as in their benzene analogues, but the thermal stability of the mesophase is somewhat less. Cyano-derivatives of pyrimidine effectively increase the value of the dielectric anisotropy of the matrix mixture, but they have a marked effect on its clarification temperature.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, 1228–1235, September,1986.     

Synthesis and photochromic properties of spiroanthrooxazine

1,3,3-Trimethylspiro[indoline-2,3-3H-anthraceno[2,1-b][1,4]oxazine] was synthesized. The compound has photochromic properties in solutions and in polymeric matrices. It was found from the spectral data that the colored form of the spiroanthrooxazine exists in a quinoid form and is characterized by a positive solvatochromic effect.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1521–1525, July, 1990.     

Synthesis and photochromic properties of 4-[2-(anthracen-9-yl)-5-methyloxazolyl] fulgide

New photochromic fulgide, viz., 4-{1-[2-(anthracen-9-yl)-5-methyloxazol-4-yl]ethylidene}-3-isopropylidenetetrahydrofuran-2,5-dione, with fluorescent properties was synthesized. Studies by electronic, IR, and ¹H NMR spectroscopy and X-ray diffraction demonstrated that this fulgide exists in the Z form. Light irradiation of its solutions at a wavelength of 365 nm causes Z/E isomerization giving rise to the thermally stable cyclic form. The latter is transformed into the starting E isomer under light irradiation at λ = 436 nm. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 97–101, January, 2006.     

Synthesis and properties of photochromic bisindolinospiropyrans

Bisspiropyrans were obtained by reaction of diquaternary salts — 1,1-polymethylenebis-(2,3,3-trimethylindoleninium) halides — or the corresponding methylene bases with 5-nitro-salicylaldehyde in the presence of piperidine. Bisspiropyrans of another type were obtained by reaction of 1-propyl-2,3,3-trimethylindoleninium iodide with 5,5-methylenedisalicylaldehyde and 5,5-methylenedi(3-nitrosalicylaldehyde). The photochemical and spectral properties of the bisspiropyrans were compared with those of the corresponding monospiropyrans.Communication VII from the series Photochromism of Organic Substances. See [1] for communication VI.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1631–1638, December, 1973.     

Synthesis and photochromic properties of novel yellow developing photochromic compounds

Two 1-thiazolyl-2-thienylcyclopentene derivatives, 1a and 2a, and a 1-thiazolyl-2-vinylcyclopentene derivative 3a have been synthesized in an attempt to obtain photochromic compounds which change the color from colorless to yellow, and have low photocycloreversion quantum yields and high absorption coefficients of the colored isomers. All of these compounds underwent reversible photochromic reactions. Compounds 1a and 2a in toluene solutions changed the color upon 313 nm light irradiation from colorless to orange and pink, in which absorption maxima were observed at 494 nm (ε=10,000 M⁻¹ cm⁻¹) and 525 nm (ε=8500 M⁻¹ cm⁻¹), respectively. On the other hand, the colorless toluene solution of 3a turned yellow upon irradiation with 313 nm light, in which the absorption maximum was observed at 416 nm (ε=17,100 M⁻¹ cm⁻¹). The photocyclization/cycloreversion quantum yields of 3 were 0.19 and 0.0014, respectively. The conversion from the open- to the closed-ring isomer of 3 in the photostationary state under irradiation with 313 nm light was close to 100%.     

Synthesis of 5-alkyl-1,3,5-triazinan-2-ones and 5-alkyl-1,3,5-triazinane-2-thiones using Cu- and Sm-containing catalysts

Efficient procedures have been developed for the synthesis of 5-alkyl-1,3,5-triazinan-2-ones and 5-alkyl-1,3,5-triazinane-2-thiones by reaction of urea (thiourea) with primary alkylamines and N,N,N′,N′-tetramethylmethylenediamine and by reaction of primary amines with N,N′-bis(dimethylaminomethyl)urea(thiourea) in the presence of Cu- and Sm-containing catalysts.     

Synthesis and properties of 1-aryl-2-alkyl-1,4,5,6-tetrahydropyrimidines

A general method is described for the synthesis of 1-aryl-2-alkyl-1,4,5,6-tetrahydropyrimidines 1 , by cyclization of N-acyl-N′-aryltrimethylenediamines 2 with trimethylsilyl polyphosphate. Precursors 2 were obtained by aminolysis of the corresponding N-(3-bromopropyl)amides 3. The ¹H nmr spectra of tetrahydropyrimidines 1 are analyzed, discussing the influence of substituents in positions 1 and 2 of the heterocyclic ring. Alkaline hydrolysis of compounds 1 , which originates exclusively N-acyl-N′-aryltrimethylenediamines 2 , through an intermediate carbinolamine, was also studied. Cleavage of such an intermediate is discussed in the light of the stereoelectronic control theory. Reduction of compounds 1 with borane, leads regiospecifically to N-alkyl-N′-aryltrimethylenediamines 6.