Five-membred 2,3-dioxoheterocycles: LXXXI. Reactions of 4,5-bis(methoxycarbonyl)-1H-pyrrole-2,3-diones with N-substituted 3-amino-5,5-dimethyl-2-cyclohex-2-en-1-ones. crystal and molecular structure of methyl 4′-hydroxy-6,6-dimethyl-1,1′-bis(4-methylphenyl)-2,4,5′-trioxo-1,1′,2,4,5,5′,6,7-octahydrospiro[indole-3,2′-pyrrole]-3′-carboxylate

1-Aryl-4,5-bis(methoxycarbonyl)-1H-pyrrole-2,3-diones react with N-substituted 3-amino-5,5-dimethylcyclohex-2-en-1-ones affording methyl 1,1′-diaryl-4′-hydroxy-6,6-dimethyl-2,4,5′-trioxo-1,1′,2,4,5,5′,6,7-octahydrospiro[indole-3,2′-pyrrole]-3′-carboxylates whose structure was proved by XRD analysis.     

Five-membered 2,3-dioxo heterocycles: LXX. Spiro heterocyclization of 1H-pyrrole-2,3-diones by the action of 1,5-binucleophiles. Crystalline and molecular structure of ethyl 1′-benzyl-7-methoxy-3,3-dimethyl-1,2′-dioxo-5′-phenyl-1′,2,2′,3,4,10-hexahydro-1H-spiro[acridine-9,3′-pyrrole]-4′-carboxylate

Ethyl 1-alkyl-4,5-dioxo-2-phenyl-4,5-dihydro-1H-pyrrole-3-carboxylates reacted with 3-arylamino-5,5-dimethylcyclohex-2-en-1-ones as carbon-centered 1,5-binucleophiles to give the corresponding substituted ethyl 1′-alkyl-3,3-dimethyl-1,2′-dioxo-5′-phenyl-1′,2,2′,3,4,10-hexahydro-1H-spiro[acridine-9,3′-pyrrole]-4′-carboxylates whose structure was proved by X-ray analysis.     

A Convenient Synthesis of 3-Aryl-3-(5,5-dimethyl-3-hydroxy-2-cyclohexene-1-one-2-yl) Propanic Esters Catalyzed by KF-Alumina

A series of 3-aryl-3-(5,5-dimethyl-3-hydroxy-2-cyclohexene-1-one-2-yl) propanic esters were synthesized by reaction of aromatic aldehydes, 5,5-dimethyl-1,3-cyclohexanedione and isopropylidene malonate in alcohols catalyzed by KF-Al₂O₃. The structure of 4a was determined by X-ray analysis.     

The Mannich reaction in the synthesis of N,S-containing heterocycles. 7. Effective one-pot synthesis of derivatives of spiro[3,5,7,11-tetraazatricyclo-[7.3.1.0<Superscript>2,7</Superscript>]tridec-2-ene-13,4′-piperidine]

5,11-Disubstituted derivatives of 1′-isopropyl-8-thioxospiro[3,5,7,11-tetrazatricyclo[7.3.1.0^2,7]tridec-2-ene-13,4′-piperidine]-1,9-dicar bonitrile was obtained by the interaction of 10-amino-9-aza-3-azonia-7,11-dicyano-3-isopropylspiro[5,5]undeca-7,10-diene-8-thiolate with 2 equiv. of a primary amine and excess of formaldehyde. An anomalous reaction product was obtained with o-toluidine — 7,9-dicyano-1′-isopropyl-3-(2-methylphenyl)-1,2,3,4-tetrahydrospiro[pyrido[1,2-a][1,3,5]triazine-8,4′-piper idinium]-6-thiolate. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, 1709–1713, November, 2007.     

2-(1-Isonicotinoylhydrazinoalkylidene)-5,5-dimethyl-1,3-cyclohexanediones and their polychromism. A new type of compound with intramolecular charge transfer through the hydrazonocarbonyl bridge

The product of condensation of 2-formyldimedone with the hydrazide of isonicotinic acid, namely 2-isonicotinoylhydrazinomethylene-5,5-dimethyl-1,3-cyclohexanedione, has been obtained in three forms — red, colorless, and yellow — which with methyl iodide give one and the same iodide 2-[N-(1-methyl-4-pyridiniumcarbonyl)hydrazinomethylene]-5, 5-dimethyl-1, 3-cyclohexanedione. On the basis of UV spectra and x-ray structure analysis of this betaine and also the dark-red iodide of N-(4-diethylaminobenzal)-N-(1-methyl-4-pyridiniumcarbonyl)hydrazine, it has been shown that intramolecular charge transfer in these linear molecules proceeds along the system of bonds D:-RC=N-NH-CO-A through the hydrazonocarbonyl bridge, which does not interrupt the conjugation chain. The existence of colored forms of the 2-isonicotinoylhydrazinomethylene-5,5-dimethyl-1,3-cyclohexanedione can be explained by an admixture of the betaine form.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 489–498, April, 1993.     

Investigation of reaction of dimedone and ethyl acetoacetate with 1,2-epoxy-3-chloropropane

Reactions of dimedone and ethyl acetoacetate with 1,2-epoxy-3-chloropropane in the presence of K₂CO₃ in DMSO medium were investigated. The reaction of 1,2-epoxy-3-chloropropane with ethyl acetoacetate afforded ethyl 5-hydroxy-2-methyl-5,6-dihydro-4H-pyran-3-carboxylate, with dimedone, 3-(1′,2′-epoxypropyloxy)-5,5-dimethyl-cyclohex-2-en-1-one.     

Synthesis of azoles from 3,3′-[(4-alkoxyphenyl)imino]bis(propanoic acid hydrazides)

Abstract  

Reaction of 3,3′-[(4-alkoxyphenyl)imino]bis(propanoic acid hydrazides) with CS₂ in alkaline solution and subsequent acidification gave 5,5′-[[(4-alkoxyphenyl)imino]diethane-2,1-diyl]bis(1,3,4-oxadiazole-2(3H)-thiones). The same dihydrazides on reaction with phenyl isocyanates or phenyl isothiocyanates were converted to bis[N′-(phenylaminocarbonyl)propanoic acid hydrazides] and bis[N′-(phenylaminocarbonothioyl)propanoic acid hydrazides], which underwent cyclization in alkaline medium to produce 5,5′-[[(4-alkoxyphenyl)imino]diethane-2,1-diyl]bis(4-phenyl-2,4-dihydro-3H-1,2,4-triazol-3-ones) and their 3-thio analogues, whereas in sulfuric acid or POCl₃ 5,5′-[[(4-alkoxyphenyl)imino]diethane-2,1-diyl]bis(N-phenyl-1,3,4-oxadiazol-2-amines) and 5,5′-[[(4-alkoxyphenyl)imino]diethane-2,1-diyl]bis(N-phenyl-1,3,4-thiadiazol-2-amines) were obtained.     

Two new isomeric lignans from <Emphasis Type="Italic">Eusideroxylon zwageri</Emphasis>

Two new lignans were isolated with two other known compounds, eusiderin A and eusiderin I, from Eusideroxylon zwageri (billian). The two new lignans have isomeric structure. The structures of the new lignans were determined to be (2R,3R,4S)-2,3-dimethyl-6,7-dimethoxy-4-ethoxy (3′,4′,5′-trimethoxybenzene)-1,5-dihydroxytetralin and (2R,3S,4S)-2,3-dimethyl-6,7-dimethoxy-4-ethoxy(3′,4′,5′-trimethoxybenzene)-1,5-dihydroxytetralin. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 303–305, May–June, 2009.     

Assignment of E/Z isomers in Schiff bases of 3-acyltetramic acids with ethylenediamine by 1H and 13C NMR spectroscopy

The reaction of ethylenediamine with an equivalent mixture of diversely substituted 3-acyltetramic acids leads to Z/Z, Z/E, E/Z and E/E isomers. The E/Z isomerisation is slow in the NMR time scale of the ¹H and ¹³C chemical shifts; therefore at room temperature and in deuterochloroform all isomers of the new synthesized asymmetric compounds N,N′-ethylene-(1-ethyl-5,5-dimethyl-1′,5′,5′-trimethyl-3,3′-acetyltetramic acid) a, N,N′-ethylene-(5,5-dimethyl-1′,5′,5′-trimethyl-3,3′-acetyltetramic acid) b and, N,N′-ethylene-(1,5,5-trimethyl-1′,5′,5′-trimethyl-3-acetyl-3′-formyl-tetramic acid) c could be found in the corresponding spectra. To assign the ¹³C NMR signals we used two-dimensional ¹³C-¹H one-bond (HMQC) and ¹³C-¹H multibond (HMBC) correlated spectroscopy and the empirical rule that CO signals involved in hydrogen bonds are shifted to a lower field. The relative stability of isomers depending on substitution pattern could be estimated from the composition of the equilibria. b crystallizes as Z/Z isomer from ethanolic solution. The X-ray structural analysis of b has shown two CH-O hydrogen bonds. Received: 31 May 1996 / Revised: 26 June 1996 / Accepted: 1 July 1996     

Five-membered 2,3-dioxoheterocycles: LXXIX. Three-component condensation of 1<Emphasis Type="Italic">H</Emphasis>-pyrrol-2,3-diones with acetonitriles and dimedone. Crystal and molecular structure of substituted spiro[chromene-4,3′-pyrrole]

5-Phenyl-4-ethoxycarbonyl-1H-pyrrole-2,3-diones react with acetonitriles and dimedone to form ethyl 2-amino-7,7-dimethyl-2′,5-dioxo-5′-phenyl-1′,2′,5,6,7,8-hexahydrospiro[chromene-4,3′-pyrrole]-4′-carboxylates. The crystal and molecular structure of ethyl 2-amino-1′-benzyl-7,7-dimethyl-2′,5-dioxo-5′-phenyl-3-cyano-1′,2′,5,6,7,8-hexahydrospiro[chromene-4,3′-pyrrole]-4′-carboxylate was proved by XRD analysis.     

Two new lead(II) coordination polymer and discrete complex containing bipyridine ligands with different positioned methyl substituents: synthesis,characterization, crystal structure determination,and luminescent properties

Lead(II) coordination polymer [Pb(5,5′-dmbpy)(μ-NO₃)₂] _n (1) and mononuclear complex [Pb(6,6′-dmbpy)(NO₃)₂] (2) (where 5,5′-dmbpy is 5,5′-dimethyl-2,2′-bipyridine and 6,6′-dmbpy is 6,6′-dimethyl-2,2′-bipyridine) were synthesized from reaction of lead(II) nitrate with 5,5′-dmbpy and 6,6′-dmbpy, respectively. Both complexes were thoroughly characterized by elemental analysis, infrared, ¹H and ¹³C NMR, UV–Vis, emission spectroscopy, as well as single-crystal X-ray diffraction. Polymer 1 possesses one-dimensional (1D) chain structure, whilst complex 2 exhibits a discrete complex which provide an extended chain parallel to the [001] direction, via weak intermolecular C–H···O hydrogen bonding. Coordination number of Pb²⁺ in 1 and 2 are 8 and 6, respectively, with the stereochemically active lone pair, resulting in the hemidirected geometry for both complexes. The nitrate anions exhibit a tridentate chelating/bridging mode in 1, and a bi-chelating mode in 2. The supramolecular features in these complexes are guided/influenced by weak directional intermolecular C–H···O hydrogen bonding (1 and 2) together with π–π and C–H···π (1) interactions. The luminescence studies of 1 and 2 confirmed that the position of methyl substituent on 2,2′-bipyridine rings has a profound effect on the fluorescence emissions.     

Investigations of the extraction equilibrium of ternary ion-association complexes of thallium(III) with ditetrazolium salts,neo-tetrazolium chloride and nitrobluetetrazolium chloride

The extraction equilibrium of ternary ion-association complexes formed between the tetrachloro complexes of thallium(III) and ditetrazolium salts, neotetrazolium chloride (NTC)[2,2′,5,5′-tetraphenyl-3-3′-(p-biphenylene)ditetrazolium chloride] and nitrobluetetrazolium chloride (NBT)[3,3′-dianizole-4,4′-bis-2-(4-nitrophenyl-5-phenyltetrazolium chloride], has been studied. As a result, the extraction constants, the distribution constants, the association constants, the distribution coefficients of thallium(III) and the extraction indicators R, have been calculated. The results have been evaluated statistically. The relative standard deviations S_r have been calculated at a statistical certainty of 95%. The ratio ditetrazolium salts/TlCl ₄ ⁻ =1∶2 has been confirmed once again.     

Unexpected formation of 6,7-dihydrobenzo[4′,5′]imidazo-[1′,2′: 1,6]pyrimido[5,4-a]indolizine derivative in the alkylation of 2-amino-1-(benzimidazol-2-yl)-3-(4-methoxybenzoyl)indolizine

An attempt to effect exhaustive alkylation of 2-amino-1-(benzimidazol-2-yl)-3-(4-methoxybenzoyl) indolizine with alkyl iodides in boiling acetone led to the formation of 6,6-dimethyl-8-(4-methoxybenzoyl)-6,7-dihydrobenzo[4′,5′]imidazo[1′,2′: 1,6]pyrimido[5,4-a]indolizine instead of expected N-alkyl derivatives. The product structure was proved by X-ray analysis.     

Five-membered 2,3-dioxo heterocycles: LXXVI. Reaction of methyl 1-aryl-3-benzoyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates with 6-amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione

Methyl 1-aryl-3-benzoyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates reacted with 6-amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione to give methyl 11-aryl-12-benzoyl-9-hydroxy-4,6-dimethyl-3,5,10-trioxo-4,6,8,11-tetraazatricyclo[7.2.1.0^2,7]dodec-2(7)-ene-1-carboxylates which underwent thermal recyclization to 1-aryl-3-benzoyl-4-hydroxy-1′,3′-dimethylspiro[pyrrole-2,5′-pyrrolo[2,3-d]pyrimidine]-2′,4′,5,6′(1H,1′H,3′H,7′H)-tetraones.     

5-Diazo-6,6-dimethyl-4-oxo-4,5,6,7-tetrahydroindazoles in [3+2] cycloaddition reactions

The [3+2] cycloaddition reactions of a series of 1,3-substituted 5-diazo-6,6-dimethyl-4-oxo-4,5,6,7-tetrahydroindazoles with maleic anhydride and dimethyl acetylenedicarboxylate gave 1′,3′-substituted 3-spiro[4,6-dioxo-4,6,3a,6a-tetrahydro-3H-furo[3,4-c]pyrazole]-5′-[6′,6′-dimethyl-4′-oxo-4′,5′,6′,7′-tetrahydroindazoles] and 1′,3′-substituted 3-spiro[4,5-di(methoxycarbonyl)-3H-pyrazole]-5′-[6′,6′-dimethyl-4′-oxo-4′,5′,6′,7′-tetrahydroindazoles] respectively. When heated the former eliminate nitrogen and are transformed into 1′,3′-substituted 6-spiro[2,4-dioxo-3-oxabicyclo[3.1.0]hexane]-5′-[6′,6′-dimethyl-4′-oxo-4′,5′,6′,7′-tetrahydroindazoles]. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1784–1791, December, 2007.     

A one-pot three-component reaction in aqueous micellar medium: an easy route to chromeno[2,3-b]quinolinedione

An efficient and green synthesis of hitherto unreported 5-aryl-3,3-dimethyl-2,3-dihydro-5aH-chromeno[2,3-b]quinoline-1,11(4H,5H)dione has been accomplished by a three-component reaction involving chromone-3-carbaldehyde, an aromatic amine, and 5,5-dimethyl-1,3-cyclohexanedione (dimedone) in 1.8 M aqueous TBAB solution. It is noteworthy that the TBAB/H₂O system can be recovered and reused for seven cycles directly.     

Reaction of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde with naphthalen-1-amine,quinolin-8-amine,and 1,3-diketones

Condensation of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde with naphthalen-1-amine and cyclohexane-1,3-dione, methyl 2,2-dimethyl-4,6-dioxocyclohexane-1-carboxylate, or dimedone gave the corresponding 7-(2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-yl)-7,8,9,10,11,12-hexahydro-12H-benzo[c]acridin-8-ones. The reaction of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde with naphthalen-1-amine and indan-1,3-dione produced 7-(2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-yl)-8H-benzo[h]indeno[1,2-b]quinolin-8-one. 7-(2′-Hydroxy-1,1′: 3′,1″-terphenyl-5′-yl)-7,8,9,10,11,12-hexahydrobenzo[b][1,10]phenanthrolin-8-ones were obtained by three-component condensation of 2′-hydroxy-1,1′: 3′,1″-terphenyl-5′-carbaldehyde with quinolin-8-amine and cyclohexane-1,3-dione, methyl 2,2-dimethyl-4,6-dioxocyclohexane-1-carboxylate, or dimedone.     

Synthesis of a Chiral 3,3′-Di- tert -butyl-2,2′-bipyrrole

 Diethyl 3,3′-di-tert-butyl-4,4′-dimethyl-2,2′-bipyrrole-5,5′-dicarboxylate was synthesized in four steps from ethyl 3,5-dimethyl-1H-pyrrole-2-carboxylate. The CH₂ hydrogens of the ethyl ester groups of the former are diastereotopic in the ¹H-NMR, consistent with axial chirality of the bipyrrole and restricted rotation about the 2,2′-bipyrrole bond, due to the tert-butyl groups. An X-ray structure of the crystalline target compound shows the pyrrole rings are twisted out of coplanarity by 84.5°.     

Study of cis-trans equilibrium of oxacarbocyanine dyes in solution and in a complex with DNA

Cis-trans equilibrium for a number of meso-substituted oxacarbocyanine dyes, 3,3′-diethyloxacarbocyanine iodide (K1), 3,3′-diethyl-9-methyloxacarbocyanine iodide (K2), 3,3′-dimethyl-9-ethyloxacarbocyanine iodide (K3), 3,3′,9-triethyl-6,6′-dimethoxyoxacarbocyanine iodide (K4), and 3,3′,9-triethyl-5,5′-dimethyloxacarbocyanine iodide (K5), has been studied in solutions and in a complex with DNA by spectral and fluorescent methods. A shift of the cis-trans isomer equilibrium toward the formation of the trans-isomer was observed in the presence of DNA, which determined in many respects the spectral effects observed upon the complexation of the oxacarbocyanine dyes. A steep rise of fluorescence (due to binding of the trans-isomer) in a complex with DNA is favorable for using oxacarbocyanine dyes to determine DNA.     

3-acyl-1,5-benzodiazepines in the reactions of 5,5-dimethyl-2-formylcyclohexane-1,3-dione with certain 1,2-diaminobenzenes

Reaction of 5,5-dimethyl-2-formylcyclohexane-1,3-dione with 4-methyl-, 4-benzoyl-, and 4-nitro-1,2-diaminobenzenes gave the corresponding 2-(2-amino-4-methylphenylaminomethylene)-, 2-(2-amino-5-benzoylphenylaminomethylene)-, and 2-(2-amino-5-nitrophenylaminomethylene)-5,5-dimethylcyclohexane-1,3-diones. When treated with hydrochloric acid, they cyclize to 7-methyl-, 8-benzoyl-, and 8-nitro-3,3-dimethyl-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepinon hydrochlorides. Under hydrolytic conditions the salts of 3,3,7-trimethyl-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepinone and 3,3-dimethyl-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepinone undergo the C₁₁−N₁₀ bond cleavage to give N-(2-aminophenyl)- and N-(2-amino-5-methylphenyl)-substituted 3-amino-2-formyl-5,5-dimethylcyclohex-2-enones. Ring opening of the hydrochlorides of 8-benzoyl-, and 3,3-dimethyl-8-nitro-2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepinones occurs at the C−N₅ bond and gives the starting enamines. Riga Technical University, Riga LV-1658, Latvia; Translated from Khimiya Geterotsiklicheskikh Soedinenii, N. 5, pp. 696–700, May, 1999.