Synthesis of substituted anthracenes, pentaphenes and trinaphthylenes via alkyne-cyclotrimerization reaction

The [2+2+2] cycloaddition reaction of 1,6-diynes 3 with 4-aryl-2-butyn-1-ols 4 and the following oxidation of the resulting benzylic alcohols to the aldehydes 1 and then treatment with an acid catalyst provided annulated anthracenes 2 in good yields.     

Partial hydrogenation of substituted pyridines and quinolines: a crucial role of the reaction conditions

Hydrogenation of pyridyl and quinolyl compounds 2-substituted with a carbonyl group (1a-c and 2b,c) using PtO₂ and 1 equiv. of HCl (conditions A) provides clean and total formation of the desired amino alcohol (hydrogenation of the heterocyclic ring and of the carbonyl) while under conditions B₁ and/or B₂ (concentrated HCl or pure CF₃CO₂H) the heterocyclic ring remains untouched and other aromatic parts are hydrogenated providing complex mixtures. When the heterocyclic ring is substituted by an alkyl group (quinaldine 3) conditions A provide mixtures while under conditions B₂ (pure CF₃CO₂H) the benzene ring is cleanly hydrogenated leading to a pure product.     

The reaction of enaminones with pentafluorobenzaldehyde. A novel route to substituted quinolines

Reaction of enaminone 1 and pentafluorobenzaldehyde ( 2 ) in glacial acetic acid afforded quinoline skeleton 3 in good yield.     

Iridium-catalyzed reaction of aroyl chlorides with internal alkynes to produce substituted naphthalenes and anthracenes

Benzoyl chlorides efficiently react with 2 equiv of dialkylacetylenes as well as diphenylacetylene in the presence of an iridium catalyst accompanied by decarbonylation to produce 1,2,3,4-tetrasubstituted naphthalenes in good yields. Use of 2-naphthoyl chlorides selectively affords the corresponding anthracene derivatives.     

Coupling of enamides with alkynes or arynes for synthesis of substituted pyridines and isoquinolines via amide activation

A novel and general procedure for Cu-catalyzed coupling of enamides with alkynes to synthesize substituted pyridines was developed. The chemistry was allowed to extend to the synthesis of substituted isoquinolines by coupling of enamides with arynes under transition-metal-free conditions.     

[60]Fullerene adducts with 9-substituted anthracenes: mechanochemical preparation and retro Diels-Alder reaction

Three 9-substituted anthracene derivatives, that is, 9-hydroxymethylanthracene (2), 9-methoxymethylanthracene (3) and bis(9-anthrylmethyl) adipate (6), were chosen as the model compounds to evaluate the reactivity in their Diels-Alder reactions with [60]fullerene and in retro Diels-Alder reactions of the formed cycloadducts. Corresponding adducts 4, 5 and 7 were prepared in high yields under solvent-free conditions using high-speed vibration milling technique. In order to determine thermal stabilities of adducts 4, 5 and 7, their dissociations in the temperature range of 40-65 °C were investigated. Fitting the dissociation rates and temperatures to the Arrhenius equation gives the activation energies of 25.8, 21.8 and 24.9 kcal/mol for compounds 4, 5 and 7, respectively.     

Direct asymmetric Mannich reaction of phthalides: facile access to chiral substituted isoquinolines and isoquinolinones

The first Mannich reaction employing phthalides using a quinidine-based multifunctional catalyst has been developed. The reported method led to the synthesis of 3,3-disubstituted phthalide derivatives in excellent yields, with good diastereo- and enantioselectivities. Convenient synthesis of chiral isoquinolinones and isoquinolines has also been demonstrated.     

Microwave-assisted synthesis of substituted phenanthrenes, anthracenes, acenaphthenes, and fluorenes

Rapid coupling reactions of polycyclic aromatic halides with various N-, S-, and Se-nucleophiles under focused microwave irradiation are described. Using this method, the desired products are obtained with good to excellent yields in a short reaction time.     

First example of ring expansion of activated quinolines and isoquinolines: novel benzoazepines

Activated quinoline and isoquinoline undergo unexpected ring expansion by diazocarbonyl compounds via C-C insertion in the presence of 5 mol% of copper triflate to produce ethyl 1H-benzo[b]azepine-1-carboxylate and ethyl 3H-benzo[d]azepine-3-carboxylate, respectively, in excellent yields with a high degree of selectivity     

Auto-tandem catalysis in the synthesis of substituted quinolines from aldimines and electron-rich olefins: cascade Povarov-hydrogen-transfer reaction

We demonstrated a catalytic cascade inverse electron demand hetero-Diels-Alder reaction (Povarov reaction) and hydrogen-transfer process. The reaction of electron-rich olefins and excess amount of imines in the presence of acid catalysts under appropriate conditions affords substituted quinolines in a single operation. In the cascade process, the catalysts, such as Tf2NH, TfOH, and Lewis acids, catalyze two mechanistically distinct reactions (auto-tandem catalysis). We also describe the synthetic utility of the prepared quinolines.     

Methods for the construction of [1,2]isoindolo-condensed benzazepines, benzazocines, quinolines, and isoquinolines. 2. Isoindoloquinolines, isoindoloisoquinolines. (Review)

Data for 1966–2004 on methods for the construction of tetracyclic systems in which an isoindole ring is condensed with quinoline and isoquinoline fragments on the [1,2] side are reviewed. Methods and conditions for the synthesis of isoindoloquinolines and isoindoloisoquinolines are examined. Examples of the synthesis of physiologically active natural alkaloids possessing the structure of these condensed isoindoles are presented. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1123–1157, August, 2006.     

Amino substituted 1-oxa-3-azabutatrienium salts: preparation, structure and reaction with carbonyl compounds

N,N-Dimethylformamide ($\text{4a}$) and N,N-dimethylpivalamide ($\text{4b}$) react with carbonyl chloride isocyanate ($\text{5}$) in the presence of antimony pentachloride to afford the amino substituted 1-oxa-3-azabutatrienium hexachloroantimonates $\text{6a}$,$\text{b}$. An X-ray diffraction analysis of $\text{6a}$ confirms the proposed structure. The heterocumulenes $\text{6a}$,$\text{b}$ react with aldehydes, ketones and tertiary carboxamides to give the amino substituted 2-azaallenium salts $\text{13a}$-$\text{O}$ in high yields.     

Methods for the construction of [1,2]isoindolo-condensed benzazepines, benzazocines, quinolines, and isoquinolines. 1. Isoindolobenzazepines, isoindolobenzazocines. (Review)

Data on methods for the construction of tetracyclic systems in which an isoindole ring is condensed with benzazepines and benzazocines on the [1,2] side are reviewed. The reaction conditions and approaches leading to isoindolobenzazepines and isoindolobenzazocines are discussed. Examples of the synthesis of physiologically active natural alkaloids with the structure of the above-mentioned condensed isoindoles are presented. Data for 1959–2004 are included. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 963–994, July, 2006.     

The reaction of thioesters with nitriles. A new synthetic approach to the preparation of substituted 4-alkylthio- and 4-arylthiopyrimidine derivatives

S-Alkyl and S-aryl thioesters react with nitriles in the presence of triflic anhydride to form substituted 4-alkylthio- and 4-arylthiopyrimidines. However, when methyl thiocyanate is used as nitrile, dithioimidocarbonates are formed. A mechanism to explain these differences is postulated.     

CuCl-catalyzed reaction of zirconacyclopentenes with oxalyl chloride: a new pathway for the preparation of cyclopentenones

Zirconacyclopentenes, which are easily prepared from alkynes and EtMgBr (or ethylene) and Cp₂ZrCl₂, reacted with oxalyl chloride in the presence of catalytic amount of CuCl to give cyclopentenones in high yields. The reaction was performed conveniently in one pot from alkynes, EtMgBr, oxalyl chloride, and Cp₂ZrCl₂.     

Studies with polyfunctionally substituted heteroaromatics: A facile route for the synthesis of polyfunctionally substituted N-aminopyridines, 1,2,4-triazolo[1,5-a]pyridines and isoquinolines

The reactions of formaldehyde and acetaldehyde with active methylene compounds, followed by reaction with cyanoacetic acid hydrazide 2, afforded N-aminopyridine-2-one derivatives 5a-f. In contrast, the reactions of cyanoacetic acid hydrazide 2 with aliphatic aldehydes and cyanothioacetamide afforded pyridinethione derivatives 11a-b. Also, the reactions of active methylene compounds with formaldehyde and cyanoacetamide afforded pyridin(1H)-2-one derivatives 12a-c. The reactions of 5b with aldehydes and ketones afforded compounds 13a, b, 14, and 15, respectively. The reactions of 5b with arylidinemalononitriles 16a,b afforded isoquinoline derivatives 19a,b. Compound 19b by hydrolysis gave the final product 20. Compound 20 could also be formed by hydrolysis of 5b to give 21, followed by the reaction with 16b. © 1997 John Wiley & Sons, Inc.     

Synthesis of N-alkylanilines and substituted quinolines by reaction of aniline with alcohols and CCl4 effected with Ni-containing catalysts

Syntheses of N-alkylanilines and 2,3-disubstituted quinolines by the reaction of aniline with CCl₄ and aliphatic alcohols under the action of nickel-containing catalysts, in particular, Ni(OAc)₂·4H₂O-Et₃N.     

Hydroxy-, amino,and mercaptopyridines and quinolines in the reaction with phenylacetylene

The 2-hydroxy-, amino-, and mercaptopyridines and quinolines react with phenyl-acetylene under different catalytic conditions with the formation of the corres-ponding O-, N-, and S-styryl derivatives. In the case of the trans isomer of 1-styryl-2-pyridone, the flat disposition of the olefin fragment and the hetero-cycle with the S-trans conformation of the sytryl group is proposed. All the cis isomers of the 1-styrylpyridones are noncoplanar.Translated from Izvestiya Akademii Nauk SSSR, Seriya. Khimicheskaya, No. 9, pp. 2098–2102, September, 1989.     

全氟丁基取代烯烃的制备及其硼氢化反应

在相转移催化或超声作用下, 全氟丁基碘和烯烃或炔烃发生加成反应, 从加成得到的烷烃脱碘化氢或烯烃加成产物脱碘还原生成全氟丁基取代烯烃. 全氟丁基取代烯烃的硼氢化反应主要得到α-全氟丁基取代的硼烷.     

A convenient procedure for the esterification of benzoic acids with phenols: a new application for the Mitsunobu reaction

The Mitsunobu reaction was found to be a convenient and effective method for the esterification of various benzoic acids with differentially functionalized phenols producing the corresponding phenyl esters in good to excellent yields.