Transformation of 1-(acyl)(2-haloethyl)amino-9,10-anthraquinones into 1-(2-acyloxyethylamino)-9,10-anthraquinones

Acylation of 1-(2-haloethylamino)-9,10-anthraquinones gave 1-[(2-haloethyl)(aroyl, hetaroyl, or acetyl)amino]-9,10-anthraquinones which were converted into the corresponding 1-[2-(aroyloxy, hetaroyloxy, or acetoxy)ethylamino]-9,10-anthraquinone on keeping in dimethylformamide. According to the experimental data (including those obtained by kinetic study), the transformation involves intramolecular migration of the acyl group through aziridinium or oxazolidinium intermediates.     

Synthesis of 2-substituted 9,10-anthraquinones

A convenient preparation of racemic 2-substituted 9,10-anthraquinones that included 2-triazoylethyl skeleton 1 and 2-alkylethyl skeleton 6 is reported. The products were obtained in good yields by a three- or four-step synthetic route based on a sequence of N-bromosuccinimide (NBS)–mediated bromination of 2-ethyl-9,10-anthraquinone 2, nucleophilic substitution, and CuI-catalyzed 1,3-dipolar cycloaddition or alkylation/reductive desulfonylation.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications^® for the following free supplemental resource(s): Full experimental and spectral details.]     

Photochemical and thermal rearrangements of 2-arylamino-1-(4-tert-butylphenoxy)-9,10-anthraquinones

Photochemical transformations of 2-arylamino-1-(4-tert-butylphenoxy)-9,10-anthraquinones involve migration of thetert-butylphenyl group either to theperi-located carbonyl oxygen to give 2-arylamino-9-(4-tert-butylphenoxy)-1,10-anthraquinones or to the nitrogen atom to give 2-aryl(4-tert-butylphenyl)amino-1-hydroxy-9,10-anthraquinones (typical products of the Smiles rearrangement). Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2519–2522, December, 1998.     

Photochemical transformations of 1-arylcyanomethyl-9,10-anthraquinones

Photochemical transformations of 1-arylcyanomethyl-9,10-anthraquinones were studied. It was established that under irradiation, the hydrogen atom of the substituted methyl group is transferred to aperi-quinoid oxygen atom to form the corresponding 9-hydroxy1, 10-anthraquinone-1-arylcyanomethides. Dark transformations of photoinduced quinonemethides result from three competing parallel processes: intramolecular transfer of the hydrogen atom, a reaction with a solvent (alcohol), and oxidation by dissolved oxygen. The kinetics of these reactions were studied.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1988–1994, October, 1995.This study was financially supported by the Russian Foundation for Basic Research (Grant No. 95-03-08920) and the Commitee for Higher Education of Russian Federation within the framework of the Chemistry program, Photochemistry course.     

A novel heterocyclization of 1-acetylenyl-9,10-anthraquinones

I-Acetylenyl-9,10-anthraquinones react with an excess of NH₂NH₂ at 80–115°C to give a mixture of substituted 7H-dibenzo[de,h]quinolin-7-ones and anthra[9,1-cd]-1,2-diazepin-8-ones. The latter compounds undergo reductive contraction of the sevenmembered ring to give the corresponding 7H-dibenzo[de,h]quinolin-7-ones. Bulky substituents in position 2 of the initial acetylenylanthraquinones prevent the formation of the sevenmembered heterocycle. A scheme of the cyclocondensation was proposed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2027–2030, October, 1998.     

Transformations of 1-amino-2-(3-hydroxyalk-1-ynyl)-9,10-anthraquinones in the presence of amines

When heated in piperidine, 1-amino-2-(3-hydroxyalk-1-ynyl)-9,10-anthraquinones undergo cyclization into 2-(1-hydroxyalkyl)naphtho[2,3-g]indole-6,11-diones. In contrast, 1-amino-2-(3-hydroxy-3-phenylpropynyl)-9,10-anthraquinone reacts with primary and secondary amines to give the corresponding 1-amino-2-(1-amino-2-benzoylvinyl)-9,10-anthraquinones, which undergo cyclization into 4-dialkylamino- or 4-alkylamino-2-phenylnaphtho[2,3-h]quinoline-7,12-diones. Heating of the starting phenylpropynol with Et₃N causes its dehydrogenation and isomerization.     

Tautomerism of metal complexes with 1,8-dihydroxy-3-R1-6-R2-9,10-anthraquinones

The structures of metal complexes with 1,8-dihydroxyanthraquinones studied by spectrophotometric, quantum-chemical, and correlation methods were found to be determined by tautomeric 9,10–1,10-anthraquinoid structures of the ligands and by the degree of the ligand ionization. Complex formation is accompanied by the shifts in tautomeric equilibria influencing both excited and ground states of the ligands. The 1,10-anthraquinoid forms of complexes are the most characteristic. The known complexes are classified in accordance with the ligand structures.     

Dual reactivity of diazonium salts derived from 1-amino-2-ethynyl-9,10-anthraquinones

Diazotization of vicinal 1-amino-2-ethynyl-4-R-9,10-anthraquinones followed by a reaction with NaN₃ gave 5-hydroxy-3-R-1H-naphtho[2,3-g]indazole-6,11-diones or 3-ethynyl-5-R-6H-anthra[1,9-cd]isoxazol-6-ones, depending on the substituents at the triply bonded C atom and in position 4 of the anthraquinone framework.     

A Quantum-Chemical Study of Prototropic Tautomerism in 1-Hydroxy-9,10-anthraquinones

The effect of substituents R on the tautomerism and electronic absorption spectra of 1-hydroxy-x-R-9,10-anthraquinones and 9-hydroxy-x-R-1,10-anthraquinones was studied by quantum-chemical and correlation methods. The former compounds (x 2) are more sensitive to substituent effects than the latter compounds. Examination of the fine structure of long-wave absorption showed that the experimental spectra of 1-hydroxy-x-R-9,10-anthraquinones contain no bands assignable to ana-quinoid forms.     

Reactions of 1-acylamino- and 1-methylsulfonylamino-2-aryloxy-4-hydroxy-9,10-anthraquinones with secondary amines

Reactions of 1-acylamino-4-hydroxy-2-phenoxy-9,10-anthraquinones with piperidine resulted in replacement of the phenoxy group by piperidino, while 1-methylsulfonyl-2-aryloxy-4-hydroxy-9,10-anthraquinones reacted with secondary amines to give products of nucleophilic substitution of hydrogen in position 3.     

Reaction of guanidine with peri-substituted (R-ethynyl)-9,10-anthraquinones bearing electron-donating substituents

2-Amino-3-aroyl-7H-dibenzo[de,h]quinolin-7-ones were synthesized by the reaction of guanidine with peri-(R-ethynyl)-9,10-anthraquinones in boiling n-butanol.     

Synthesis of Novel 1-(substituted phenyl)-2-phospholene 1-Oxide Derivatives

Several novel 1-(substituted phenyl)-2-phospholene 1-oxide derivatives, which are analogs of sugars having a phosphorus atom in place of the ring oxygen of normal sugars, were synthesized from the corresponding 2-phospholenes as the starting materials. Structures of all the synthesized compounds were unequivocally confirmed by IR, 1 H, 13 C, and 31 P NMR spectral, elemental, and X-ray crystallographic analyses.     

Tricarbonylchromium complexes of some substituted 9,10-dihydro-9,10-o-benzenoanthracenes

Tricarbonylchromium complexes of 9,10-dihydro-l,4-dimethoxy-9,10-o-benzenoanthracene and 9,10-dihydro-l,4-dimethyl-9,10-o-benzenoanthracene have been prepared and characterized. Under the given experimental conditions, the dimethoxy ligand forms two isomeric complexes. These have been separated by both analytical and preparative scale liquid chromatography. Structures have been tentatively assigned on the basis of experiments with the NMR shift reagent EuFod₃. The methyl substituted ligand forms three isomeric complexes.     

Optisch aktive 1- und 2-substituierte 9,10-Dihydro-9,10-äthanoanthracene

Zusammenfassung Racematspaltung der 9,10-Dihydro-9,10-äthanoanthracen-1-und 2-carbonsäuren bzw.-(-oxobuttersäuren) (2 a, 2 b bzw.8 a, 8 b) und geeignete Folgereaktionen machten optisch aktive monosubstituierte Derivate von 9,10-Dihydro-9,10-äthanoanthracen,1 (wie die Acetyl-, Formyl- und Methylderivate) sowie aus den buttersäuren9 (erhalten aus8) auch cyclische Ketone (10 und11) zugänglich. Die konfigurative Korrelation der beiden Reihen (a undb) gelang über die Schlüsselsubstanz (+)-1,2,3,4,7,12-Hexahydro-7,12-äthanobenzo[a]-anthracen (12), woraus sich auch die optische Reinheit aller Folgeprodukte ergab.Die absolute Konfiguration wurde durch kinetische Racematspaltung sowohl der Carbonsäure2 a als auch eines mit2 a (und2 b) korrelierten Carbinols14 (nachHoreau) für alle beschriebenen Derivate von1 als (+)-(9R) ermittelt.Neben den []_D-Werten wurden auch dieCD-Spektren einiger Derivate von1 gemessen. Diese chiroptischen Daten werden kurz diskutiert.

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Optically active 1- and 2-substituted 9.10-dihydro-9.10-ethanoanthracenes; Preparation, chiroptical properties, configurational correlations and absolute configurations

Optically active monosubstituted derivatives of 9.10-dihydro-9.10-ethanoanthracene (1)—such as the acetyl, formyl and methyl derivatives—were prepared by optical resolutions of the carboxylic acids2 a and2 b and the -oxobutyric acids8 a and8 b, resp., and suitable subsequent reactions, whilst from the butyric acids9 (accessible from8) also cyclic ketones (10 and11) were obtained. The configurative correlation of both series (a andb) was achievedvia the key substance (+)-1.2.3.4.7.12-hexahydro-7.12-ethanobenzo[a]anthracene (12) wherefrom also the optical purities of all compounds were deduced.The absolute configurations of all described derivatives of1 were established as being (+)-(9R) by kinetic resolutions both of the carboxylic acid2 a and of a carbinol14 (correlated with2 a and2 b) according toHoreau's method.Besides the []_D-values also theCD-spectra of some typical derivatives of1 were recorded. These chiroptical properties are briefly discussed.

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Mit 1 Abbildung     

Cascade Transformations of 1-R-Ethynyl-9,10-anthraquinones with Amidines: Expanding Access to Isoaporphinoid Alkaloids

The interaction of acetamidine and phenylamidine with peri-R-ethynyl-9,10-anthraquinones in refluxing n-butanol leads to the formation of cascade transformations products: addition/elimination/cyclization―2-R-7H-dibenzo[de,h]quinolin-7-ones and(or) 2-R-3-aroyl-7H-dibenzo[de,h]quinolin-7-ones. The anti-inflammatory and antitumor properties of the new 2-R-7H-dibenzo[de,h]quinolin-7-ones were investigated in vivo, in vitro, and in silico. The synthesized compounds exhibit high anti-inflammatory activity at dose 20 mg/kg (intraperitoneal injection) in the models of exudative (histamine-induced) and immunogenic (concanavalin A-induced) inflammation. Molecular docking data demonstrate that quinolinones can potentially intercalate into DNA similarly to the antitumor drug doxorubicin.     

A new electrochromic material from an indole derivative and its application in high-quality electrochromic devices

A novel electrochromic material, poly(indole-6-carboxylic acid) (PIn), and its application in electrochromic devices (ECDs) are discussed. PIn was switched between yellow in the reduced state and green in the oxidized state. Electrochromic switching of PIn film shows that it has fast switching time and high optical contrast. ECD based on PIn and poly(3,4-ethylenedioxythiophene) (PEDOT) was also fabricated and characterized. The response time of this device was found to be 1.0 s and the optical contrast was 45%. The coloration efficiency (CE) was calculated to be 510 cm² C^?1. Clear change from green (neutral) to blue-violet color (oxidized) of ECD is demonstrated with robust cycle life. These results provide an avenue for applications of polyindole family in electrochromic devices.     

Darstellung und Protenenresonanz-Spektren von 1- und 2-substituierten 9,10-Dihydro-9,10-äthanoanthracenen

Zusammenfassung Für stereochemische Untersuchungen wurden mehrere 1- und 2-substituierte 9,10-Dihydro-9,10-äthano-anthracene (wie die Carbonsäuren, Acetyl-, Formyl- und Methyl-derivate sowie-buttersäuren) dargestellt. DieFriedel-Crafts-Acylierung von1 führt überwiegend zur Substitution in Stellung 2, die isomeren 1-Substitutionsprodukte sind durch Umsetzung geeigneter Anthracenderivate mit Äthylen (und entsprechende Folgereaktionen) zugänglich. Cyclisierung der Buttersäuren9 lieferte die isomeren -Oxo-hexahydro-äthanobenzoanthracene.Die NMR-Spektren der beschriebenen Berbindungen werden kurz diskutiert; zur Erkennung des Substitutionstyps sind die Resonanzen der Brückenkopf-Protenen (an C-9 und C-10) besonders geeignet.

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Preparation and proton magnetic resonance spectra of 1- and 2-substituted 9.10-dihydro-9.10-ethanoanthracenes

For stereochemical investigations several 1- and 2-monosubstituted 9.10-dihydro-9.10-ethanoanthracenes (such as the carboxylic acids, acetyl, formyl and methyl derivatives as well as butyric acids) were prepared.Friedel-Crafts acylation of1 leads to substitution predominantly in position 2; the isomeric 1-substitution products are accessible by reaction of suitable anthracene derivatives with ethylene (and subsequent transformations). Cyclizations of the butyric acids9 yield the isomeric -oxo-hexahydro-ethanobenzoanthracenes.The n.m.r. spectra of the compounds described are briefly discussed; for the identification of the type of substitution the resonances of the bridgehead protons (at C-9 and C-10) are especially suitable.

     

First TDAE approach in quinonic series: synthesis of new 2-substituted 1,4-dimethoxy-9,10-anthraquinones

We report herein an original preparation of 2-substituted 1,4-dimethoxy-9,10-anthraquinones using the first example of TDAE strategy in quinonic series. This TDAE approach is an original and mild method to generate a quinonic anion, which cannot be formed via organometallic strategy.     

Chameleonic reactivity of vicinal diazonium salt of acetylenyl-9,10-anthraquinones: synthetic application toward two heterocyclic targets

The nature of products in the diazotization of 1-amino-2-acetylenyl-9,10-anthraquinones strongly depends on the nature of substituents at both the alkyne and at the anthraquinone core. Donor substitution (NHAr, OH) at the fourth position stabilizes the diazonium salt at C1, decelerating electrophilic cyclization at the arylethynyl substituent at C2. This effect allows the replacement of the diazonium with azide group and subsequent closure into isoxazole ring with preservation of the alkyne. In contrast, electrophilic 5-exo-dig cyclizations to condensed pyrazoles is observed for the combination of donor substituents at the aryl alkyne moiety and an OAc substituent at C4. The latter process provides a new synthetic route to 3-ethynyl-[1,9-cd]isoxazol-6-ones that are difficult to access otherwise. DFT calculations suggest that donor substituents have only a minor effect on alkyne and diazonium polarization in the reactant but provide specific transition state stabilization by stabilizing the incipient vinyl cation. This analysis provides the first computational data on electrophilic 5-exo-dig cyclization in its parent form and the nucleophile-promoted version. This cyclization is a relatively fast but endothermic process that is rendered thermodynamically feasible by the enol-keto tautomerization with concomitant aromatization in the five-membered heteroaromatic ring. Computations suggest that the importance of nucleophilic assistance in the transition state for a relatively weak nucleophile such as water is minor because the energy gain due to the Lewis base coordination to the carbocationic center is more than compensated for by the unfavorable entropic term for the bimolecular proces.