Preparation and reactivity of metal-containing monomers

The stability constants of some bi- and trivalent metal complexes with methyl-, trifluoromethyl-, and phenyl-substituted 6-heptene-1,3-diones have been determined by pH-metric titration at 20 °C and an ionic strength = 0.1. It is proposed that vinyl groups of ligands are involved in complexation.For Part 44 seeIzv. Akad. Nauk, Ser. Khim., 1995, 1827 [Russ. Chem. Bull., 1995,44, 1758 (Engl. Transl.)].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2404–2408, December, 1995.This work was partially financially supported by the International Science Foundation (Grant No. NJB000).     

1,3-Dipolar cycloaddition of diazocyclopropane to strained cycloalkenes and conjugated dienes to give spiro(1-pyrazoline-3,1′-cyclopropanes)

Polycyclic spiro(1-pyrazoline-3,1-cyclopropanes) were obtained in 32–70 % yields by the reaction of diazocyclopropane generatedin situ with 2-methyltricyclo[3.2.1.0^2,4]oct-6-ene, spiro[2,4]hepta-4,6-diene dimer, benzvalene, spiro[2,3]hex-1-ene, methyl 1-methylcyclopropene-3-carboxylate, buta-1,3-diene, and 2-methylbuta-1,3-diene.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2199–2202, November, 1995.This study was financially supported by the Russian Foundation for Basic Research (Grant No. 94-03-08902).     

Polyfluorinated hydrazones in organic synthesis

Oxidation ofN,N-unsubstituted 1,1,1,5,5,5-hexafluoro-4-trifIuoromethylpentane-2,3-dione bishydrazone with sulfuryl chloride or bromine in CCl₄ gives 1-amino-5-trifluoromethyl-4-(1,1,1,3,3,3-hexafluoroisopropyl)-1,2,3-triazole in high yield. Its structure has been confirmed by X-ray structural analysis.For Part 1 see Ref. 1.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No.12, pp. 2465–2467, December, 1995.The work was supported by the Russian Foundation for Basic Research (Project Nos. 94-03-08548 and 94-03-08338) and the International Science Foundation (Grants NDL 000 and NDL 300).     

Reaction of stereoisomeric bis(cyclohexyl)-2,2′-diones with hydrogen peroxide: structure of the formed adducts

The reaction ofmeso- andD,L-forms of bis(cyclohexyl)-2,2-dione with a methanol solution of hydrogen peroxide in a neutral medium has been studied. It has been established that in the case of theD,L-formrac-(1R,4R,9S,10S)-1,4-dihydroxy-2,3-dioxatricyclo-[8.4.0.0^4,9] tetradecane is formed, while themeso-form affordsrac-(1R,4R,9S,10R)-1-methoxy-4-hydroxy-2, 3-dioxatricyclo[8.4.0.0^4,9]tetradecane. The structures of the compounds have been established by X-ray structural analysis and by¹H and¹³C NMR spectroscopy.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 934–939, May, 1995.This work was financially supported by the International Science Foundation (Grant M04 000), the American Crystallographic Association, and the Russian Foundation for Basic Research (Project No. 94-03-09189).     

Synthesis of formyl derivatives of benzocrown ethers containing N,S, and O heteroatoms in the macrocycle

A method for the synthesis of 4-bromobenzodithia-15(18)-crown-5(6) and 4-bromobenzodiaza-15 (18)-crown-5(6) by condensation of 3,4-di(2-haloethoxy)bromobenzene with polyoxaalkanes containing terminal SH or NHMe groups was suggested. The method for the synthesis of formyl derivatives of benzocrowns containing N, S, and O heteroatoms in the macrocycle based on the metallation of appropriate bromo derivatives with BuⁿLi followed by treatment of the resulting organolithium intermediates with DMF was developed. Oximes and semicarbazones of benzaldehydes containing a crown ether fragment were obtained, and their transformation into the original aldehydes by treatment with KNO₂ in an acid medium was studied.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 121–128, January, 1995.This study was financially supported by the Russian Foundation for Basic Research (Grant No. 94-03-08-531) and the International Science Foundation (Grant M8Q000).     

Thermal decomposition of strained spiro(1-pyrazoline-3,1′-cyclopropanes)

Pyrolysis (320–370 °C) of polycyclic 1-pyrazolines1 and2, obtained by 1,3-dipolar cycloaddition of diazocyclopropane to 3,3-dimethylcyclopropene and spiro[2,3]hex-1-ene, yields complex mixtures of isomeric hydrocarbons, substituted methylenecyclopropanes being the main components. Pyrolysis of 6-ethenyl- (4) and 6-methoxy-6-methylcarbonyl-4,5-diazaspiro[2,4]hept-4-enes (6) at 310–320 °C proceeds more unambiguously to give vinyl- (18) and 1-methoxy-1-methylcarbonylspiropentanes (20) in 85 and 95 % yields with respect to the transformed pyrazolines. Dediazotization of pyrazoline3 obtained from diazocyclopropane and benzvalene requires more drastic conditions (–440 °C) and produces indane.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2203–2207, November, 1995.This study was financially supported by the Russian Foundation for Basic Research (Grant No. 94-03-08902).     

Synthesis of bisalkenyl ethers by the reaction of 1,1,2,2-tetracyanoethane with α-alkylacroleins in isopropyl alcohol

The reaction of 1,1,2,2-tetracyanoethane (1) with -alkylacrole ins in isopropyl alcohol affords 3-alkyl-2-amino-3-(isopropoxy)hydroxymethyl-1,5,5-tricyanocyclopentenes (2a,b) and 2,7-dialkyl-1,8-diisopropoxy-4,4,5,5-tetracyanoocta-1,7-die nes (3a,b). The structure of molecule3b has been established by X-ray structural analysis.Deceased in 1995. mis Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 246–247, January, 1996.     

Structural features and the nature of the hydrogen bond in the enol form of α-diphenylphosphoryl-α-acetylacetonitrile based on X-ray diffraction data

It has been established by X-ray structural analysis that pure -diphenylphosphoryl--acetylacetonitrile exists in the enol form (aZ isomer). In crystals, a strong intramolecular P=O...H...O hydrogen bond is formed; the O...O distance is 2.551 Å. It has been demonstrated that the H atom is characterized by a high lability along the hydrogen bond, which exhibits a covalent component in the H...O region.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1520–1524, August, 1995.The X-ray structural study was supported by the American Crystallography Association and the International Science Foundation (Grant No. M1F000).     

Acylation of spiro(1-pyrazoline-3,1′-cyclopropanes) to form 1-acyl-3-(2-chloroethyl)-2-pyrazolines and transformation of bicyclic 2-pyrazolines into 1,4,5,6-tetrahydropyridazines

Strained polycyclic spiro(1-pyrazoline-3,1-cyclopropanes) react with acetyl or benzoyl chlorides at 0–15 °C regioselectively to give in high yields corresponding 1-acyl-3-(2-chloro-ethyl)-2-pyrazolines. Under the same conditions 6-ethenyl-4,5-diazaspiro[2,4]hept-4-ene gives a mixture of two pyrazolines resulting from the acyl group attack directed at different nitrogen atoms. Bicyclic pyrazolines-2 obtained by acylation of the cycloaddition products of diazocyclopropane with 3,3-disubstituted cyclopropenes transform under the action of hydrogen chloride to 1,4,5,6-tetrahydropyridazines in high yields.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2208–2211, November, 1995.The work was carried out with financial support of the Russian Foundation for Basic Research (Grant No. 94-03-08902).     

Dichotomy in the reaction between cinnamyl dithiocarboxylates and tetracyanoethylene with the formation of 7,8-dithiabicyclo[3.2.1]octanes and dithioacyloxycyclopentanes

The reaction of cinnamyl dithiocarboxylates (1) containing electron-donating substituents at the central carbon atom of the dithioester group (R = p-MeOC₆H₄, EtO, andp-Tol) with tetracyanoethylene affords 2,2,3,3-tetracyano-4-endo-phenyl-7,8-dithiabicyclo[3.2.1]octanes (2) as well as isomeric 3,3,4,4-tetracyano-2-phenyl-trans-1-dithioacyloxycyclopentanes (3). Dithiabicyclooctanes2 rearrange to the corresponding cyclopentanes3 upon thermolysis.Dedicated to Academician of the RAS N. S. Zefirov (on his 60th birthday).Deceased in August, 1995.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1804–1808, September, 1995.This work was supported by the Russian Foundation for Basic Research (Project No. 93-03-04290), the International Science Foundation and the Russian Government (Grant M5Y 300), and the Russian State Committee on Higher Education (Scientific and Technical Program Fine Organic Synthesis, Project FT-12).     

X-ray structural study of the first bicluster π-arene complex [η6-PhCo4(CO)9]2CH2 and binuclear complex [η6-PhCr(CO)3]2CH2

It has been established by X-ray structural study that the bicluster cobalt -arene complex of diphenylmethane [⁶-PhCo₄CO₉]₂CH₂ and binuclear complex [⁶-PhCr(CO)₃]₂CH₂ have ans-trans-s-trans conformation in their crystals.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1111–1117, June, 1995.This work was supported by the Russian Foundation for Basic Research (Projects No. 93-03-4028 and 94-03-08338).     

Conformational peculiarities of a new heterocyclic dihydrothienothiopyranoisoxazole system

The crystalline and molecular structures of 3H-3a,4-dihydro-7-methylthieno[3,2:5,6]thiopyrano[4,3-c]isoxazole and 3H-3a,4-dihydro-3-isopropoxycarbonyl-3a,7-dimethylthieno[3,2:5,6]thiopyrano[4,3-c]isoxazole are determined by X-ray analysis. The effect of steric factors on intramolecular 1,3-dipolar cycloaddition is shown.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 302–304, February, 1995.This work was financially supported by the Russian Foundation for Basic Research (Project No. 93-03-18461).     

β-Substituted cyclopropyl rádicals grafted to silica surface. Methods of preparation,structure, and properties

Cyclopropyl type radicals were identified on a surface of activated silica by ESR. The possibility of their preparation by two methods,i.e., by photocyclization of substituted allyl radicals and by interaction of cyclopropane molecules with particular surface defects, was demonstrated. The effects of -substituents on radiospectroscopic characteristics and thermal stabilities of the radicals were studied. Rate constants and activation energies of decomposition of substituted cyclopropyl radicals were estimated. The experimental data obtained were compared with the results of quantum-chemical calculations of model systems. The mechanism of photocyclization of allyl radicals was discussed. The transition states of decomposition of cyclopropyl and -fluorine-substituted cyclopropyl radicals were calculated. Electronegative substitution was found to result in a considerable decrease in the activation energy of the cyclopropane ring opening.The authors are grateful to E. G. Baskir for calling their attention to this publication.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2409–2421, December, 1995.The work was carried out with financial support of the Russian Foundation for Basic Research (Project code 94-03-09137) and the International Science Foundation (Grant No. MK9000).     

Convenient preparative method for synthesis of methyl (Z)-3-aryl-2-(carbobenzoxyamino)acrylates by Wittig—Horner reaction with the use of Et3N as a base

The Wittig—Horner reaction of CbzNHCH(CO₂Me)P(O)(OMe)₂ (1) with ArCHO (2) in the presence of Et₃N as a base affords methyl (Z)-3-aryl-2-(carbobenzoxyamino)acrylates (3) with high degrees of diastereoselectivity (Z)/(E) > 101. One recrystallization of the crude product is sufficient to obtain isomerically and chemically pure (Z)-3.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2218-2220, November, 1995.The authors are grateful to the Dupont company (USA) for financing this study     

Synthesis and ozonization of (+)-4α-(1-trimethylsilyloxyethen-1-yl)-2-carene

(+)-4-(1-Trimethylsilyloxyethen-1-yl)-2-carene was synthesized, and the products of its ozonization were identified.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1984–1987, October, 1995.     

Photochemical addition of diethyl ether to β,β,β',β'-tetrakis(trifluoromethyl)divinyl ether

The 1:1 adducts of diethyl and ,,','-tetrakis(trifluoromethyl)divinyl ether (1),i.e., 3,5-(ee)-bis[2,2,2-trifluoro-1-(trifluoromethyl)ethyl]-2,6-dimethyl-1,4-dioxane (2) (3 isomers) and 4-ethoxy-1,1,1-trifluoro-2-trifluoromethyl-3-[3,3,3-trifluoro-2(trifluoromethyl)propenyloxy]pentane (3), have been obtained by UV-irradiation of a solution of divinyl ether1 in diethyl ether. The X-ray structural investigation of the all-(e)-isomer of dioxane (2) has been carried out.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 85–88, January, 1994.     

Ethyl 3,3-diamino-2-(2-p-tolylpyrimidin-4-yl)acrylate,a new representative of hetarylketene aminals

A new representative of hetarylketene aminals, ethyl 3,3-diamino-2-(2-p-tolylpyrimidin-4-yl)acrylate, was synthesized by the reaction ofp-toluamidine with the condensation product of dimethylformamide dimethyl acetal and the difluoroboron chelate of acetyl(ethoxycarbonyl)ketene (N-benzoyl)aminal. This synthesis is an example of pyrimidine ring assembly using the methodology based on transformations of chelate complexes.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1638–1640, September, 1994.This research was partially supported by the International Science Foundation (Grant No. M5QOOO).     

Quantum-chemical study of the molecular and electronic structure of 2,2′-dithiodi(2-methyl-2,3-dihydro-1,4-thiazino[2,3,4-i,j]quinolinium)

Conformational isomerism of 2,2-dithiodi(2-methyl-2,3-dihydro-1,4-thiazino[2,3,4-i,j]quinolinium) has been studied by semiempirical MNDO and AM1 methods. Six symmetrical and unsymmetrical stationary states have been found. Optimum intramolecular rotations around single bonds have been considered. The possibility of the inversion of the reaction centers in nucleophilic and electrophilic reactions depending on the conformational state of the molecule has been shown. The spatial structure of one of the conformers found is similar to that typical of (–)-cystine. The observed constancy of some geometric and electronic parameters makes it possible to study the principal physicochemical properties of dithiazinoquinolinium compounds by the most sophisticatedab initio methods using small model structures, which are constructed by taking into account the variability of other geometric parameters, as an example.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2359–2364, December, 1995.The work was supported by the Russian Foundation for Basic Research (Project No. 93-03-18400).     

Synthesis and molecular structure of 3-bromo-trans-2,6-diallyl-Δ3-piperideine hydrochloride

The structure of 3-bromo-trans-2,6-diallyl-³-piperideine hydrochloride was determined by X-ray diffraction analysis. The corresponding base was prepared by reductive diallylation of 3-bromopyridine with triallylborane. 3-Bromo-cis-2,6-diallyl-₃-piperideine3 was prepared by heatingtrans-isomer2 with triallylborane at 130 °C followed by deboronation of the resulting aminoborane with a solution of sodium hydroxide.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 705–707, April, 1994.This work was carried out with the financial support of the Russian Foundation for Basic Research (project No 93-03-18193).     

Synthesis of ω-(2-oxocyclododecyl)alkanoic acids by alkylation of cyclododecanone with ω-haloalkanoic esters under conditions of phase-transfer catalysis

(-(2-Oxocyclododecyl)alkanoic acids have been obtained by alkylation of cyclododecanone with alkyl 3-bromopropionate, 5-iodopentanoate, and 11 -bromoundecanoate under conditions of phase-transfer catalysis.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2521–2523, December, 1995.