Benzazetines and their derivatives (review)

Published information on methods for the production of benzazetines and their dehydro derivatives (benzazetes) and their chemical transformations is reviewed and analyzed. It was noted that benzazetines with an unsubstituted NH group are unstable and their stable representatives have only became accessible in recent years. The tendency of benzazetines to undergo opening of the four-membered heterocycle and isomerization processes was demonstrated. The wide-ranging synthetic possibilities of benzazetines and benzazetes are indicated. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1763–1783, December, 2007.     

2-Aminooxazoles and their derivatives (review)

The literature data on methods for the synthesis of 2-aminooxazoles and their benzo derivatives and their physicochemical properties and transformations are correlated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1011–1024, August, 1981.     

Polyfuryl(aryl)alkanes and their derivatives

The reduction of 2-nitrophenyldifurylmethane with SnCl₂ leads to an indolenyl ketone as a result of intramolecular heterocycloaddition of the intermediately formed nitroso derivative. During the reduction of 2-nitroaryldifurylmethanes in the Zn+HCl or NH₂NH₂·H₂O+Pd/C systems, 2-aminoaryldifurylmethanes are formed; when treated with trityl perchlorate, their acetyl derivatives are converted into indolo[2,3-h]-1-oxazulenium perchlorates.For Communication 14, see [1].Kubansk State Technological University, Krasnodar. Severo-Osetinsk State University, Vladikavkaz. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1614–1621, December,1997.     

Polyfuryl(aryl)alkanes and their derivatives. 4. Synthesis of furyldiarylmethane derivatives

A number of substituted furyldiarylmethanes were obtained by the reaction of furan derivatives with secondary aromatic alcohols.See [1] for Communication 3.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 307–308, March, 1984.     

N-acyl (substituted) phenylglycine derivatives

Amidoalkylation of three benzoheterocycles, benzimidazole-2-one, 1,3-dihydrobenzo[c]-thiophene 2,2-dioxide and 1,3-dihydro-2,1,3-benzothiadiazole using N-acylhippuric acids was successful. The corresponding phenylglycine analogs were prepared by removal of the N-acyl protecting group.     

Etheno derivatives of adenine and cytosine (review)

The method of modification of heterocyclic bases of nucleic acids with chloroacetaldehyde and other α-halo carbonyl compounds is examined in this review. The mechanism, kinetics, and scope of the reaction, the chemical properties of modified derivatives of adenine and cytosine, and the possibilities of the application of etheno derivatives of adenine and cytosine in biochemistry and molecular biology are discussed. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 291–305, March, 1980.     

Organotin (IV) derivatives of L-cysteine and DL-penicillamine

The preparations of chlorodimethyl- and chlorodi-η-butyl tin(IV) derivative of L-cysteine, L-cysteine ethyl ester and DL-pencillamine are described. Infrared, n.m.r. and mass spectral data are presented. The compounds contain SnS bonds and suggestions for structures are made.     

Synthesis and characterization of poly(vinylcyclohexane) derivatives

Six nearly monodisperse substituted poly(styrene) homopolymers, poly(styrene) (PS), poly(2-methylstyrene) (P2MS), poly(3-methylstyrene) (P3MS), poly(4-methylstyrene) (P4MS), poly(tertiary-butylstyrene) (PtBS), and poly(α-methylstyrene) (FαMS) were anionically polymerized and subsequently saturated using heterogeneous hydrogenation techniques to poly(vinylcyclohexane) (PVCH), poly(2-methylvinylcyclohexane) (P2MVCH), poly(3-methylvinylcyclohexane) (P3MVCH), poly(4-methylvinylcyclohexane) (P4MVCH), and poly(tertiary-butylvinylcyclohexane) (PtBVCH), respectively. In each case, except PαMS, the materials were saturated to > 99% conversion with no chain degradation. PS hydrogenations required the addition of small amounts of tetrahydrofuran to the reaction solvent cyclohexane to enhance miscibility and eliminate large-scale chain degradation. Density gradient and differential scanning calorimetry (DSC) measurements were used to characterize the density and glass transition temperature, T_g, of the unsaturated and saturated polymers. Saturation reduces the density by 3% to 11% and changes T_g substantially. The greatest variation in T_g is obtained with the 3-methyl substituted species where a 63°C increase is observed, while the highest measured T_g is 186°C for P2MVCH. Small-angle neutron scattering (SANS) experiments on binary mixtures of hydrogenous and deuterium labeled PVCH derivatives provided a determination of bulk chain statistics. The statistical segment length is relatively insensitive to vinylcyclohexane ring substitution, except with P3MVCH where a 20% greater value is obtained. ©1995 John Wiley & Sons, Inc.     

U(VI) Complexes of oxine and derivatives

Infrared bands due to the hydrogen-bonded (+)N-H cdots, three dots, centered O system in the oxine adduct of U(VI) have been identified and found to occur in the spectra of several newly prepared U(VI) adducts of oxine derivatives. Interligand steric effects in the U(VI) complexes of most 7-substituted oxines prevent the formation of the 1:3 adduct. Complexes of the type ML(2)X, where X is a small co-ordinating species present in solution, are formed instead. With 2-substituted oxines, steric interactions between the 2-substituent and co-ordinated water result in destabilization of the complex and subsequent hydrolysis as the pH of the solution is raised. Experiments involving the use of [(14)C]-oxine were found to distinguish between co-ordinated and lattice-held oxine and are potentially valuable in studies of oxine adducts formed by other metal ions.     

Ditolyldithiophosphato derivatives of phosphorus(III) and phosphorus(V)

O,O′-Ditolylphosphorodithioates of phosphorus(III), [(o-, m-, or p-CH₃C₆H₄O)₂PS₂] _n PCl_3−n , and phosphorus(V), [(o-, m-, or p-CH₃C₆H₄O)₂-PS₂] _n POCl_3−n , (n = 1, 2, and 3) were isolated as colorless viscous liquids by the reaction of PCl₃ and POCl₃ with sodium ditolylphosphorodithioate, (o-, m-, or p-CH₃C₆H₄O)₂PS₂Na, in 1:1, 1:2, and 1:3 molar ratios in toluene. These compounds were characterized by elemental analyses, molecular weight measurements, IR, and NMR (¹H, ³¹P, and ¹³C) spectroscopic studies, which indicated a less common monodentate linkage of dithiophosphate moieties in both phosphorus(III) and phosphorus(V) derivatives leading to a tetrahedral geometry around the phosphorus atom.     

(2,2,2-Trinitroethoxy)acetic acid and its derivatives

The influence of the trinitromethane salt cations and the substituents in the alkyl moiety of chloromethyl ethers of alcohols on the yields of trinitroethyl ethers of the substituted alcohols formed from them was established. On this basis a representative series of previously unavailable trinitroethanol ethers was synthesized.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2540–2544, November, 1991.     

Ditolyldithiophosphato derivatives of phosphorus(III) and phosphorus(V)

O,O′-Ditolylphosphorodithioates of phosphorus(III), [(o-, m-, or p-CH₃C₆H₄O)₂PS₂] _n PCl_3−n , and phosphorus(V), [(o-, m-, or p-CH₃C₆H₄O)₂-PS₂] _n POCl_3−n , (n = 1, 2, and 3) were isolated as colorless viscous liquids by the reaction of PCl₃ and POCl₃ with sodium ditolylphosphorodithioate, (o-, m-, or p-CH₃C₆H₄O)₂PS₂Na, in 1:1, 1:2, and 1:3 molar ratios in toluene. These compounds were characterized by elemental analyses, molecular weight measurements, IR, and NMR (¹H, ³¹P, and ¹³C) spectroscopic studies, which indicated a less common monodentate linkage of dithiophosphate moieties in both phosphorus(III) and phosphorus(V) derivatives leading to a tetrahedral geometry around the phosphorus atom. Correspondence: Sushil K. Pandey, Department of Chemistry, University of Jammu, Baba Saheb Ambedkar Road, Jammu 180 006 (J & K), India.     

Difluoro(pentafluorothio)acetic acid and its derivatives

Russian Chemical Bulletin -     

Organic derivatives of antimony. IV. Association of alkoxy and chloroalkoxy derivatives of antimony (III) and (V)

Russian Chemical Bulletin -     

Synthesis of chiral SalenZn(II) and its coordination with imidazole derivatives and amino acid ester derivatives

A chiral complex, SalenZn(II) (S), was synthesized and characterized. Its coordination with imidazole derivatives and amino acid ester derivatives was studied by UV-vis spectrophotometric titrations and CD spectroscopy. The binding constants decreased in the order K (Im)>K (2-MeIm)>K (2-Et-4-MeIm)>K (N-MeIm) for imidazole derivatives, and K (AlaOMe)>K (PheOMe)>K (ValOMe) for amino acid ester derivatives with the same configuration and K _D >K _L for amino acid esters with different configuration. CD spectra can quantify the strength of SalenZn(II)-ligand interactions, giving results consistent with the magnitudes of the binding constants. Moreover the minimum energy conformations of the adducts were obtained by simulated annealing, and quantum chemical calculations were performed based on those conformations to explain experimental results at the molecular level.     

Trimethylsilylmethyl derivatives of thallium(III)

Some trimethylsilylmethyl derivatives of thallium(III) have higher stability and unusual coordination behavior in comparison with simple alkylthallim(III) analogs for steric reasons.