Condensation of N-monosubstituted 2-naphthylamines,formaldehyde, and cyclic β-diketones. One-pot synthesis of 2,4-disubstituted derivatives of 1,2,3,4-tetrahydrobenzo[<Emphasis Type="Italic">f</Emphasis>]quinoline

Various spirocyclic derivatives of 1,2,3,4-tetrahydrobenzo[f]quinoline containing substituents in the positions 2 and 4 of the ring were obtained by one-pot multicomponent condensation of available N-benzyl-2-naphthylamines, formaldehyde, and cyclic β-diketones of cyclohexanedione series.     

Synthesis and spectral-luminescence properties of some substituted 1,3-diarylbenzo[f]quinolines

Amino derivatives of 1,3-diarylbenzo[f]quinoline were synthesized and subjected to reaction with methyl vinyl ketone in the presence of catalytic amounts of concentrated HCl to give the corresponding (3-oxobutyl) aminophenyl derivatives. The electronic absorption and fluorescence spectra were studied, and the absolute fluorescence quantum yields of the synthesized compounds were determined. A relationship between the position and intensity of the absorption bands and the electron-donor substituents was uncovered, and a substantial effect of the nature of the solvent on the fluorescent spectra was established.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 116–120, January, 1976.     

Simple synthesis of benzo[f] pyrrolizidine and benzo[g]indolizidine with the use of products of the reductive allylation of indole and quinoline

Benzo[f]pyrrolizidine and benzo[g]indolizidine were synthesized by hydroboration-oxidation-intramolecular cyclization of the corresponding products of the reductive -allylation of indole (2) and quinoline (6) with allylboranes.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No, 11, pp. 2807–2809, November, 1996,     

Hemicyanines from 3-arylbenzo [f] quinolinium salts and their spectral-luminescence properties

1-(-Anilinovinyl)-3-arylbenzo[f]quinolinium methiodides were synthesized by the condensation of 1,4-dimethyl-3-arylbenzo[f]quinolinium salts with ethyl orthoformate and aniline or by fusion with N,N-diphenylformamidine. The IR spectra, the absorption spectra in the visible region, and the fluorescence of the dyes in the crystalline state were examined. The introduction of substituents in the 3-phenyl ring of benzo[f]quinoline gives rise to a bathochromic shift of the fluorescence band.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 969–971, July, 1980.     

Quantum yields of [W(CN)8]4− formation in charge-transfer photochemistry of octacyanotungstate (V)

Summary The reactions of monochromatically photolyzed aqueous [W(CN)₈]^3– solutions in the pH range 1–13 were found to consist of a two-step sequence involving a primary inter-molecular redox process and a consecutive thermal chain process, both leading to the formation of octacyanotungstate(IV) as the main reaction product. The initial quantum yields, ₀, are practically constant for the entire pH range and equal to 0.81±0.05 mole/Einstein. The final quantum yields, _f, for both neutral and alkaline solution, were found to be greater than 1, having also an approximately constant value of 3.42±0.25. The empirical rate law for the post-irradiation reaction under excess of [W(CN)₈]^3– and at constant pH is given by: rate = k_obs[R]²[W(CN) ₈ ^4– ]^–2 where R is a one-electron reductant. Kinetic data suggest a mechanism of the Haber-Weiss type for the thermal reduction of [W(CN)₈]^3– by H₂O₂.     

Alkaloids ofHaplophyllum foliosum. II.

In addition to the alkaloids known previously from this plant, haplofoline and folifine, from the epigeal part ofHaplophyllum foliosum we have isolated norgraveoline with mp 288–289°C (decomp. from acetone), and myrtopsine with mp 201–202°C (from chloroform), []_D-5° (c 0.05; methanol), which were first obtained fromHaplophyllum dubium andMyrtopsis sellingii, respectively. We have confirmed by the PMR-spectroscopic method the positions of the substituents in the dihydrofuran ring of myrtopsine suggested previously on the basis of biogenetic considerations. In addition, it has been established that the substituents are present in the trans form. This is the first time that myrtopsine has been detected in plants of the genusHaplophyllum.Institute of the Chemistry of Plant Substances of the Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 613–616, September–October, 1981.     

Zur Synthese von 4-Aminochinolinen durch intramolekulareFriedel—Crafts-Reaktion

Treatment of arylaminomethylene-malononitriles,-cyanoacetamides and--cyanoacetophenones with AlCl₃ yields substituted 4-aminoquinolines2, while quinolin-4-ones3 are obtained from ethyl arylaminomethylene cyanoacetates. N--naphthylcyanoacetamide reacts in the presence of AlCl₃ to form 1-amino-3-benzo[f]quinolinone (6). Isothiazolo[4,3–c]quinolines (10) and pyrimido[5,4–c]quinolines (11, 12) can be obtained from2. 4-Aminoquinoline-3-carboxylic acids derived from2, can be decarboxylated.3 are cyclized to form oxazino[5,6–c]-quinolinones (4).     

Spectral-luminescence characteristics of 1,3-diaryl-4,7-phenanthrolines

The effect of the nature of the substituents and the solvent on the absorption and fluorescence spectra and the fluorescence quantum yields of 1,3-diaryl-4,7-phenanthrolines was studied. Electron-donor groups in the para position of the phenyl ring cause a bathochromic shift of the absorption and fluorescence spectra and an increase in the fluorescence quantum yields. A change in the polarity of the solvent leads to a significant shift of the fluorescence spectra of hydroxy and dialkylamino derivatives of 4,7-phenanthroline.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1651–1654, December, 1987.     

Synthesis and Properties of Bis(naphthofuran)-Fused [7]Helicene Derivatives

Novel benzo[1,2-b:4,3-b′]dinaphthofuran (oxa[7]helicene) with various substituents in the central ring were designed and successfully synthesized based on the late stage central ring formation strategy from naphthofuranoneby using an efficient McMurry coupling or Friedel-Crafts acylation. The photochemical properties of helicenes were evaluated by UV-Visible absorption spectroscopy and fluorescence spectroscopy, while electrochemical behaviour including their energy profile were investigated by cyclic voltammetry and DFT calculations. According to the computational study, substituents on the central ring could influence both electron delocalization and MO distribution of oxa[7]helicenes resulting in the change in charge transporting ability. In comparison to the parent carbo[7]helicene, the furan unit in conjunction with substituents on helical system caused the bathochromic shift with different absorption pattern and exhibited higher fluorescence quantum yield (ϕ_f up to 0.63). These new materials showed promising characteristics in optoelectronic application.     

Saturated heterocycles, 75. Preparation of tetracyclic thiophene derivatives with bridgehead nitrogen. Synthesis of polymethylenethieno[2,3—d]dihydropyrrolo-, tetrahydropyrido- and tetrahydroazepino[1,2—a]pyrimidin-4-ones and -4-thiones

The following tetracyclic ring systems and their derivatives have been synthesized for pharmacological investigations: Trimethylenethieno[2,3—d]dihydropyrrolo[1,2—a]pyrimidin-4-one and -4-thione (1 a, 5 a); Tetramethylenethieno[2,3—d]dihydropyrrolo[1,2—a]pyrimidin-4-one and -4-thione (1 b, 1 j, 5 b); Pentamethylenethieno[2,3—d]dihydropyrrolo[1,2—a]pyrimidin-4-one and-4-thione (1 c, 5 c); Trimethylenethieno[2,3—d]tetrahydropyrido[1,2—a]pyrimidin-4-one and -4-thione (1 d, 5 d); Tetramethylenethieno[2,3—d]tetrahydropyrido[1,2,—a]pyrimidin-4-one and -4-thione (1 e, 5 e); Pentamethylenethieno[2,3—d]tetrahydropyrido[1,2—a]pyrimidin-4-one and -4-thione (1 f, 5 f); Trimethylenethieno[2,3—d]tetrahydroazepino[1,2—a]pyrimidin-4-one and -4-thione (1 g, 5 g); Tetramethylenethieno[2,3—d]tetrahydroazepino[1,2—a]pyrimidin-4-on and -4-thione (1 h, 5 h); Pentamethylenethieno[2,3—d]tetrahydroazepino[1,2—a]pyrimidin-4-one and -4-thione (1 i, 5 i); Tentamethylenethieno[2,3—d]tetrahydroazepino[1,2—a]pyrimidin-4-one (7 b); Pentamethylenethieno-[2,3—d]tetrahydropyrido[1,2—a]pyrimidin-4-one (7 c).Compounds1 a–i were synthesized from 2-amino-3-ethoxycarbonyl-4,5-polymethylenethiophene2 a–c with the corresponding lactim ethers (3 a–c) in chlorobenzene in the presence of polyphosphoric acid (PPA). Compounds7 b and7 c were obtained in the reaction of -amino acid esters2 b and2 c with 2-bromopyridine (6). The thione derivatives (5 a–i) were prepared from compounds1 a–i with phosphorus(V) sulphide.Part 74:Szabó J, Fodor L, Szcs E, Bernáth G, Sohár P (1984) Pharmazie 39: 347.     

The synthesis of novel polycyclic heterocyclic ring systems via photocyclization. 9. Phenanthro[9′,10′:4,5]thieno[2,3-c]quinoline,benzo[f]phenanthro[9′,10′:4,5]thieno[2,3-c]quinoline,and benzo[h]-phenanthro[9′,10′:4,5]thieno[2,3-c]quinoline

The synthesis of three novel polycyclic heterocyclic ring systems are reported via photocyclization. The specific final products in these ring systems are: phenanthro[9′,10′:4,5]thieno[2,3-c]quinoline ( 13 ), benzo[h]-phenanthro[9′,10′:4,5]thieno[2,3-c]quinoline ( 14 ), and benzo[f]phenanthro[9′,10′:4,5]thieno[2,3-c]quinoline ( 15 ).     

Synthesis, structure, and biological activity of [2.2]paracyclophanes. 7. Synthesis of 2-([2.2]paracyclophan-4-yl)pyridines,-tetrahydroquinolines, and-benzo[h]quinolines based on condensation of 4-(β-dimethylaminopropionyl)[2.2]paracyclophane with primary amines

Condensation of 4-(-dimethylaminopropionyl)paracyclophane with aliphatic aldehydes or cyclohexanones in the presence of hydroxylamine gave 2-([2.2]paracyclophan-4-yl)pyridines and-5,6,7,8-tetrahydroquinolines respectively. Reaction of these salts with -naphthylamine gives a mixture of paracyclophanyl substituted 1,2,3,4-tetrahydrobeno[h]quinoline and benzo[h]quinoline.For Communication 6, see [1].Russian University of National Friendship, Moscow 117198. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1069–1073, August, 1997.     

Reaction of acetyltetramic acid witho-phenylenediamine

Acetyltetramic acid forms 3-[-(2-aminophenylamino)ethylidene]-2,4-pyrrolidinedione (Ia) witho-phenylenediamine. NMR spectroscopy showed that compound Ia in solutions of CDCl₃ and DMSO exists as an equilibrium mixture of two rotational isomers caused by hindered rotation around an exocyclic double bond. The analysis of the¹³C NMR spectra of compounds of type I and the results of quantum chemical calculations indicate preferred chelation of amide carbonyl and predominance of the corresponding rotamer. The reaction of a Ia with hydrochloric acid yields 10-methyl-1H-benzo[b]pyrrolo[3,4-f]-1,4-diazepin-1-one.Riga Technical University, Riga LV-1658; Latvian Institute of Organic Synthesis, Riga LV-1006; Institute of Bioorganic Chemistry, Academy of Sciences of Belarus' Minsk 220141. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp336–342, March, 1995. Original article submitted December 29, 1994.     

Iodine‐Catalyzed Synthesis of Cyclopenta[c]quinoline Derivatives via Imino Diels–Alder Reaction

A mild and efficient method for the synthesis of cyclopenta[c]naphtho[2,3‐f]quinoline and cyclopenta[c]pyrazolo[4,3‐f]quinoline derivatives via an imino Diels–Alder reaction of aromatic aldehyde, anthracen‐2‐amine, or 1H‐indazol‐5‐amine and cyclopentanone catalyzed by iodine is described. This novel procedure has the advantages of mild reaction condition, high yields, and metal‐free catalyst.     

6,6-Heptamethylenetetrahydropyran-2,4-dione in the Synthesis of Benzo[f]pyrano[3,4-b]quinolines and Pyrano[4,3-b][4,7]phenanthrolines

Three-component condensation of 6,6-heptamethylenetetrahydropyran-2,4-dione with 2-amino-naphthalene or 6-aminoquinoline and aromatic aldehydes in an aliphatic alcohol afforded 12-aryl-9,9-hepta-methylene-8,9,10,12-tetrahydro-7H-benzo[f]pyrano[3,4-b]quinolin-11-ones and 12-aryl-9,9-heptamethylene-8,9,10,12-tetrahydro-7H-pyrano[4,3-b][4,7]phenanthrolin-11-ones, new N,O-heterocycles which include azaor diazaphenanthrene system fused to -pyrone ring and aromatic and spiro substituents.     

Z‐Shaped Pyrrolo[3,2‐b]pyrroles and Their Transformation into π‐Expanded Indolo[3,2‐b]indoles

Sterically hindered 1,4‐dihydropyrrolo[3,2‐b]pyrroles possessing ortho‐(arylethynyl)phenyl substituents at positions‐2 and ‐5 were efficiently synthesized through a sila‐Sonogashira reaction. These unique Z‐shaped dyes showed relatively strong fluorescence in solution. Detailed optimization revealed that, in the presence of InCl₃, these alkynes readily undergo an intramolecular double cyclization to give hexacyclic products bearing an indolo[3,2‐b]indole skeleton in remarkable yields. Steady‐state UV–visible spectroscopy revealed that upon photoexcitation, the prepared Z‐shaped alkynes undergo mostly radiative relaxation leading to high fluorescence quantum yields. In the case of 7,14‐dihydrobenzo[g]benzo[6,7]indolo[3,2‐b]indoles, we believe that the substantial planarization of geometry in the excited state, is the underlying reason for the observed large Stokes shifts. The presence of additional electron‐withdrawing groups makes it possible to further alter the photophysical properties. The two‐photon absorption cross‐section values of both families of dyes were found to be modest and the nature of the excited state responsible for two‐photon absorption appeared to be strongly affected by the presence of peripheral groups. Serendipitous synthesis of unusual double‐Z‐shaped alkyne by Sonogashira and Glaser coupling is also reported.     

Spectral-luminescence properties and basicities of 2-(4-pyridyl)-5-(4-r-phenyl)oxazoles

The spectral-luminescence and acid-base properties of 2-(4-pyridyl)-5-(4-R-phenyl)oxazoles were studied. Significant -electron conjugation between the individual fragments exists in the molecules of these compounds in solutions at room temperature. Bathochromic and bathofluoric effects, which are particularly appreciable for electron-donor substituents, are observed when substituents R are introduced into the 5-phenyl ring. Ethanol solutions of the investigated compounds have high fluorescence quantum yields which, for some of them, are close to unity. Electron-donor substituents R increase the basicity of the pyridine nitrogen atom.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 479–482, April, 1985.     

Spectral,luminescent, and photophysical properties of dipyrrolylbenzenes

Dipyrroles with a phenylene bridge, 1,4-bis(pyrrol-2-yl)benzene, 4-(1-vinylpyrrol-2-yl)-1-(pyrrol-2-yl)benzene, and 1,4-bis(1-vinylpyrrol-2-yl)benzene, show intense room-temperature fluorescence in solutions. Analysis of electronic absorption spectra, fluorescence spectra, and results of B3LYP, TD B3LYP, and CIS quantum chemical calculations showed that the introduction of a bulky substituent in position 1 of the pyrrole ring makes the ground-state structures of dipyrrolylbenzenes less planar. Excited-state geometries of all molecules relax to more planar conformations. An increase in the probability of nonradiative transitions has little effect on the quantum yields of fluorescence (Φ_f) of dipyrrolylbenzenes. Even for 1,4-bis(1-vinylpyrrol-2-yl)benzene, where the pyrrole rings deviate from the benzene ring plane by 44°, the fluorescence efficiency remains high enough (Φ_f = 0.7). Substitution at nitrogen atoms has little effect on positions of fluorescence band maxima. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1433–1438, July, 2008.     

Spin-orbit coupling of ππ* states in molecules with annelated oxazole ring

Within the framework of the -electron approximation, matrix elements have been calculated for the operator of spin-orbit coupling (SOC) between singlet and triplet terms of oxazole derivatives with condensed naphthalene, quinoline, coumarin, and carbostyryl fragments (24 structures were examined). Values calculated for the SOC have been compared with experimentally measured quantum yields of fluorescence for 15 compounds. It has been established that the values of the SOC matrix elements amount to 0.02–0.03 cm^–1 on the average.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 26, No. 4, pp. 403–406, July–August, 1990.     

Pyrazolo[1,5-a]pyrimidine-Dioxaborinine Hybrid Dyes: Synthesis and Substituent Effect in the Photophysical Properties

A novel family of pyrazolo[1,5-a]pyrimidine-dioxaborinine (PP-DB) hybrid dyes was synthesized by the direct construction of the dioxaborinine (DB) fragment on the pyrazolo[1,5-a]pyrimidine (PP) ring, which implies the formation of four new bonds in a one-pot manner. The dyes’ optical properties were investigated and compared with the starting pyrazolo[1,5-a]pyrimidines; a study evidencing large fluorescence quantum yields in products (φ_f up to 69 %) due to an intramolecular charge transfer (ICT) process from the PP core to a ring of DB (PP→DB) that is absent in precursors (φ_f=0.03–0.30). Time-dependent density functional theory (TD-DFT) calculations confirmed the fluorescence process involved in the novel dyes, where their ICT limits the non-radiative process due to the restricted rotation in the D−A system. The present work provides insight into how phenyl and DB ring incorporation impact the optical properties of this new group of hybrids dyes based on PP-DB.