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Oxidation of ethyl cyanoglyoxylate 2-oxime followed by KOH treatment affords stable potassium salt of nitroacetonitrile which is a reliable substitute of hazardous free nitroacetonitrile in organic synthesis.

It is demonstrated, that 1,3-benzoxazin-4-ones react with Vilsmeier reagent to give chromene derivatives in generally good yields.

A novel one-pot procedure for accessing the comparatively little studied title compounds (III) is reported.

A the great number of the title compounds is prepared in good yields via a novel procedure from aminofurazanyl hydroximoyl chlorides and o-diaminobenzenes.

We offer a systematic and generalized review of literature data over the previous 10 years regarding the synthesis of monocyclic and condensed 1,3,5-thiadiazine derivatives under the conditions of Mannich reaction.

A new approach to benzo-annelated δ-sultams containing an aryl–nitrogen bond is described. The method, which involves the intramolecular Michael cyclization of tert-butyl ortho-[N-(methoxycarbonylmethyl)sulfonylamino]cinnamates, allows the synthesis of secondary sultams as well as their tertiary analogues and bridged tricyclic derivatives efficiently and diastereoselectively.

The reaction of 3-benzoylquinoxalin-2(1H)-ones with enamines (generated in situ from ammonium acetate and the corresponding methylaryl(hetaryl)ketones) proceeds smoothly to give the corresponding substituted 1-(pyrrolyl)benzimidazolone derivatives in moderate yields through the novel rearrangement of 3-benzoylquinoxalin-2(1H)-ones involving a dual cleavage of the C3═N4 and C2-C3 bonds under mild conditions.

Besides amino acids, which react under through decarboxylation, alkyl amines, diamines, and aminoalcohols serve as aminomethylene sources.

3-Substituted methyl 3,4-dihydroisocoumarin-6-carboxylates were obtained by the intramolecular cyclization of 2,5-dimethoxycarbonyl benzenediazonium bromides with methyl/ethyl acrylate and styrenes under Meerwein's arylation conditions.

The synthesis of a variety of 3-halo-2-methylpyrimidobenzimidazolones and their behavior in alkylation reactions are described.

Single crystals of Cs2NaBi(MoO4)3 are grown by annealing (673-773 K, 60 h) of a mixture of Na2MoO4 (obtained via calcination of the hydrate), Cs2MoO4 (obtained by annealing Cs2CO3 and MoO3, 823 K, 60 h), and Bi2(MoO4)3 (obtained by reacting Bi2O3 and MoO3, 723-773 K, 50 h).

The rearrangement process includes a novel ring contraction as the key step to produce various benzimidazole structures bearing a pyrrole part at one of the nitrogens.

A novel, regioselective method for the synthesis of the title compounds (VI) as structural analogues of unnatural nucleosides is developed.

Colorless, blocklike crystals of the title cluster, envisioned as a solution-processable material for thin film electronics, are prepared by slow evaporation of a mixture of Ga(NO3)3 dissolved in MeOH and N-nitrosodibutylamine in air at room temperature.

A reaction of N-methylmorpholinium 6-amino-4-aryl-3,5-dicyano-1,4-dihydropyridine-2-selenolates with primary amines and excess of formaldehyde leads to 3,5,7,11-tetraazatricyclo[7.3.1.02,7]tridec-2-ene-8-selenone derivatives. The same compounds were obtained by a multicomponent cascade cyclocondensation of benzaldehyde, cyanoselenoacetamide, primary amine, and excess of formaldehyde.

Title compounds are synthesized from materials which are easily available from plant extracts.

Cyanothioacetamide reacts with pyrazole-3(5)-diazonium chlorides to afford pyrazolo[5,1- c ][1,2,4]triazine-3-carbothioamides 5 . The latter can be oxidized with H 2 O 2 to give either pyrazolo[5,1- c ][1,2,4]triazine-3-carboxamides or 1,2,4-thiadiazole derivatives, depending on the reaction conditions. The Hantzsch-type reaction of thioamides 5 with α-bromo ketones leads to 3-(thiazol-2-yl)pyrazolo[5,1- c ][1,2,4]triazines.

Optically active compounds are the key elements of natural systems such as living organisms. Therefore, the production of such compounds is of prime importance, especially in the fields of pharmaceuticals, agrochemicals, and so on. Furthermore, novel and emerging approaches to supramolecular chemistry, nanoscience, biomimetics, and sensing also require optically active molecules of high enantiopurity. Several methods, such as optical resolution and catalytic and enzymatic asymmetric syntheses, have been developed thus far to obtain enantiomeric compounds. Of these approaches, heterogeneous chiral catalysis is one of the most promising techniques for the large-scale production of enantiopure compounds, featuring facile preparation, simple separation, and easy recovery and reuse of the catalyst, as well as the timeand cost-saving, environmentally benign methods. Practically, there are two most effective heterogeneous catalytic systems for enantiodifferentiating hydrogenation: (1) cinchona alkaloid-modified metallic platinum and palladium catalysts and (2) tartaric acid (TA)-modified nickel catalysts. Both catalysts give high enantioselectivities for specific prochiral substrates. The platinum-based chiral catalysts hydrogenate activated ketones, such as a-ketoesters, ketopantolactones, pyrrolidinetriones, aketoacetals, a-ketoethers, a-diketones, and other related compounds, in 95–98% ee, whereas the modified palladium catalysts reduce a,b-unsaturated carboxylic acids and alkene derivatives in 90–94% ee. In contrast, the TA-modified nickel catalysts prepared in the presence of NaBr reduce b-ketoesters and 2-alkanones and give the corresponding alcohols in up to 98 and 85% ee, respectively. In the preparation of TA-modified nickel catalyst, activated metallic nickel powders, such as Raney nickel, reduced nickel (prepared by the reduction of nickel oxide), supported nickel, and activated commercial nickel powder, 34] are commonly used. The commercially available nickel powder is usually activated through treatment with hydrogen stream at an elevated temperature, which is followed by the chiral modification by immersing the activated nickel powder into an aqueous solution containing TA and NaBr. The hydrogen pretreatment is not necessary if the commercial nickel powder is used as a nickel base, because the modification solution (containing TA and NaBr) is adjusted to pH 3.2 and thus it can remove the oxidized material from the nickel surface. Thus, the TA-NaBr solution plays dual roles of cleaning and modifying the nickel surface to afford a smooth surface structure appropriate for the enantiodifferentiation by removing defects. This risk-free surface activation without using the hydrogen pretreatment is an important step toward the large-scale production and application of chirally modified nickel catalysts in industry. Herein, to establish the protocol for preparing highly efficient TA/NaBr-modified nickel catalysts without preactivation, The chirally modified nickel catalysts for the enantiodifferentiating hydrogenation of b-ketoesters are prepared conventionally by immersing hydrogen-activated metallic nickel into an aqueous solution of enantiopure tartaric acid, in which the preactivation of nickel is essential. Herein, we revealed that even commercially available nickel powders without any pretreatment can catalyze the enantiodifferentiating hydrogenation of b-ketoesters to give the corresponding b-hydroxyesters in quantitative yield and high enantioselectivity (up to 91%) under optimized conditions. The immediate use of commercially available nickel powders and the reproducible high chemical and optical yields not only expand the scope of heterogeneous asymmetric catalysis but also pave the way for the practical application and industrial use of chirally modified nickel catalysts.

Reaction of cyanoselenoacetamide with 1,3-dicarbonyl compounds bearing 2-anilinomethylene derivatives provides access to a variety of novel pyridine- and guinoline-containing selenium compounds as structural analogous of biologically active substances.

The title compounds (V) are obtained by a mediated Hantzsch-type multicomponent reaction of cyanoselenoacetamide (I) with aromatic aldehydes and 1,3-cyclohexanedione in the presence of an excess N-methylmorpholine.

New types of 1,1,1-trialkyl-2-alkoxyhydrazinium chlorides and N-alkoxyhydrazines were obtained by reactions of N-chloro-N-alkoxy- ureas with trimethylamine or 1,4-diaza[2.2.2]bicyclooctane and by reactions of methyl N-chloro-N-methoxycarbamate with potassium salt of N-acetylbenzenesulfonylamide. The XRD studies of N,N’-bis(methoxycarbonyl)-N,N’-dimethoxyhydrazine, N’-methoxy- N’-methoxycarbonyl-N-acetylbenzenesulfonylhydrazide and 1,1,1-trimethyl-2-methoxyhydrazinium perchlorate revealed the pyramidal configuration of the central nitrogen atoms in O–N–N geminal system, unusual elongation of N–N+ bond and shortening of N–OMe bond in 1,1,1-trimethyl-2-methoxyhydrazinium perchlorate.

A new, catalyst-free, domino Knoevenagel–hetero-Diels–Alder elimination oxidation reaction is reported. 5-Aryl-2H,6H-chromeno[4′,3′:4,5]thiopyrano[2,3-d][1,3]thiazol-2-ones are formed in moderate to good yields via reaction of 2-(3-aryl-3-chloro-2-propenyloxy)benzaldehydes with 4-thioxo-1,3-thiazolidin-2-one.

Brief heating of 3-aryl-2-cyanothioacrylamides in the DMSO–HCl system gave (2E,2′E)-2,2′-(1,2,4-thia-diazol-3,5-diyl)bis(3-arylacrylonitriles). Under the same conditions, cyclic thioamides (derivatives of 2-thioxo-1,2-dihydropyridine-3-carbonitrile and quinoxaline-2(1H)-thione) gave good yields of the bis(hetaryl) disulfides. Ethyl 4-(4-chlorophenyl)-5-cyano-2-phenyl-6-thioxo-1,4,5,6-tetra-hydropyridine-3-carboxylate gave a mixture of oxidation products at the sulfur atom and the hetero-cycle when treated with the DMSO–HCl system. Oxidation of N-aryl-4,6-dimethyl-2-thioxo-1,2-di-hydropyridine-3-carboxamides gave isothiazolo[5,4-b]pyridines.

RbLn[Ge(CN2)4] (I) (Ln: La, Pr, Nd, Gd) and RbLn[Si(CN2)4] (II) are prepared by solid state metathesis reaction of stoichiometric mixtures of LnCl3, Rb2[GeF6] or Rb2[SiF6], and Li2(CN2) (evacuated silica ampoule, for (I): 450 °C, 1 d; for (II): 550 °C, 2 d).

The interaction of 3-amino-3-thioxopropanamides with 2-anilinomethylene derivatives of dimedone, 1,3-cyclohexanedione and Meldrum’s acid led to the formation of 2-(2-amino-2-oxoethyl)-6-thioxo-1,6-dihydropyrimidine-5-carboxamides. The latter were alkylated in alkaline medium with the formation of 4-(alkylthio)pyrimidine-5-carboxamide derivatives.

Coumarins, analogues of natural antimitotic compounds, are synthesized and tested in vivo in the phenotypic sea urchin embryo assay for antiproliferative antitubulin activity.

Refluxing (I) with P4S10 in dry pyridine affords the title compounds as stable pyridine complexes.

Ethoxymethylene compounds are quite widely used in heterocyclic synthesis as three-carbon 1,3-dielectrophilic synthons [7, 8], but only isolated examples are known of their use in preparing selenium-containing compounds [9-11]. As has been noted [9], in contrast to their sulfur-containing analogs, the preparation of Se-containing derivatives in an analytically pure state can be difficult in such reactions.

β-Enaminocarbonyl compounds are commonly used in heterocyclic synthesis as convenient and readily available 1,3-dielectrophile 3C synthones [1, 2]. In previous work [3], we showed that the reaction of 5,5-dimethyl-2-phenylaminomethylidenecyclohexane-1,3-dione (1) with cyanothioacetamide gives the quinoline derivative 2. We established that the reaction of thiomalonamide 3 with dimedone derivative 1 yields 6-thioxopyrimidine-5-carboxamide 4 instead of the expected 3-carbamoyl analog of quinoline 2. Alkylation of carboxamide 4 with benzyl chloride gives benzyl derivative 5. The structures of carboxamides 4 and 5 were supported by IR, H-NMR, and C-NMR spectroscopy, HPLC/MS, elemental analysis, and the results of a H-C HMBC NMR experiment for carboxamide 4 (Fig. 1). The H NMR spectrum of carboxamide 4 shows signals for two amide groups and one methylene group, as well as singlets for protons H-4 and NH. The HPLC/MS shows a peak [M+H] with m/z 213.6. Atom H-4 in the pyrimidine ring in the H-C HMBC spectrum gives four correlation peaks: δ-8.78/127.1 (H-4/C-5), 8.78/159.6 (H-4/C-2), 8.78/163.7 (H-4/5-CONH2), and 8.78/179.7 ppm (H-4/C-6). The CH2 group protons give two cross peaks: δ-3.69/159.6 (CH2/C-2) and 3.69/167.8 ppm (CH2/CO). The finding of cross peaks at δ 7.17/41.1

The Mannich reactions of (arylmethylidene)(cyano)selenoacetamides with primary amines and formaldehyde gave 3,7-disubstituted 8-R-3,4,7,8-tetrahydro-2H,6H-pyrimido[4,3-b]-[1,3,5]selenadiazine-9-carbonitriles. Alternatively, these compounds can be obtained by reactions of 4-R-2,6-diamino-4H-selenopyran-3,5-dicarbonitriles with primary amines and form-aldehyde or by multicomponent condensation of an appropriate aldehyde, cyanoselenoacet-amide, a primary amine, and formaldehyde.

Pyrido[2,1-b][1,3,5]thiadiazines are a rather rare type of condensed heterocyclic system [1-3], and only isolated studies reporting the preparation of this bicyclic system have been reported [4-6]. We have shown that treatment of the previously synthesized 4-methyl-6-oxo-2-thioxopiperidine-3-carbonitrile 1 [7] with primary amines in the presence of excess HCHO gives the previously unknown pyrido[2,1-b][1,3,5]thiadiazines 2a,b. The structure of compounds 2a,b was confirmed from H NMR and IR spectroscopy and from elemental analysis data. The potential of the method and its optimization will be the subject of further investigations.

The present new method constitutes a simple and efficient route to thiazine and thiazole derivatives.

The title compound is prepared by solid state reaction of a stoichiometric mixture of Pr6O11 and TiO2 (1100 °C, 300 h) and characterized by XRD and SEM.

The method is efficient procedure for the synthesis of 4-aryl substituted Guareschi imides.

The title compounds (x = 0.25, 0.5, 0.75, 0.9) are prepared by solid state reaction of Al(NO3)3, H3BO3, K2CO3, and Rb2CO3 (various heat treatments between 400 and 850 °C for 7—48 h).

The title catalytic system as an uncharged nanosized catalytic complex gives high yields (≥90%) of the aerobic cross-coupling reaction of aryl halides and phenylboronic acid at 25 °C.

This feature article gives a general introduction to the phenomenon of supramolecular chirogenesis using the most representative examples of different chirogenic assemblies on the basis of ethane-bridged bis-porphyrinoids. Supramolecular chirogenesis is based upon a smart combination of supramolecular chemistry and chirality sciences and deals with various aspects of asymmetry induction, transfer, amplification, and modulation. These chiral processes are governed by numerous noncovalent supramolecular forces thus allowing a judicious, mechanistic, and dynamic control by applying a variety of internal and external influencing factors. Currently, supramolecular chirogenesis is widely used in different fields of fundamental and applied branches of science and modern technology, touching on such important issues as origin of chirality on the Earth, asymmetry sensing, enantioselective catalysis, nonlinear optics, polymer and materials science, pharmacy and medicine, nanotechnology, molecular and supramolecular devices, chiral memory, absolute configuration determination, etc.

Some isochromane derivatives exhibit hypotensive,1 antitumor,2 and growth-regulating3 activities; some others have a specific effect on the dopaminergic system.4

A variety of new aminofurazans is designed, synthesized and evaluated for their antimitotic activity using a sea urchin embryo assay.

A new cis-form of ethylene-bridged octaethylporphyrin dimer 3a has been obtained by isomerization of the corresponding trans-isomer 2a . On the basis of spectral data the structure of 3a was assigned to be close to a “face-to-face” orientation. Reflecting the peculiar structure of 3a UV-vis and 1 H NMR spectra are remarkably distinguished from those of ordinary porphyrins.

Carbanions formed from malononitrile and ethyl cyanoacetate have been found to react with pyridinium salts via ring-opening to form 1,1,7,7-tetrasubstituted hepta-1,3,5-trienes.