Phenanthrene-fused azo-ene-ynes: synthesis of dibenzo[f,h]cinnoline and dibenzo[e,g]isoindazole derivatives

The cyclization reactions of a phenanthreno-fused azo-ene-yne compound have been studied both experimentally and computationally. Experimental results show that this system is prone to dimerization, more so than previously studied naphthalene- and benzene-based analogues. Calculations reveal that pyrazoles and arene-fused pyrazoles strongly stabilize carbenes in the 5-position through "coarctate conjugation", suggesting a stationary concentration of the carbenes/carbenoids during cyclization that is high enough for dimerization.     

Synthesis of 2,7-Diazabicyclo[3.3.0]octane and 2,7-Diazabicyclo[3.3.0]oct-4-ene Derivatives via Cyclization Reaction and Julia Reaction

2,7-Diazabicyclo[3.3.0]octan-4-ol (1) and 2,7-diazabicyclo[3.3.0]oct-4-ene (2) are synthesized by the desulfonylation using Mg-HgCl₂(cat.) of β-hydroxy sulfone derivatives which have been prepared via cyclization of sulfone ester derivative.     

The synthesis of novel polycyclic heterocyclic ring systems via photocyclization. 22 Dibenzo[f,h]benzothieno[2,3‐c]quinoline,dibenzo[f,h]benzothieno[2,3‐c][1,2,4]triazolo[4,3‐a]quinoline and dibenzo[f,h]naphtho[2′,1′:4,5]thieno[2,3‐c]quinoline

Photocyclization of 3‐chloro‐N‐(9‐phenanthryl)benzo[b]‐thiophene‐2‐carboxamide ( 3 ) and 3‐chloro‐N‐(9‐phenanthryl)‐naphtho[1,2‐b]thiophene‐2‐carboxamide ( 10 ) yielded dibenzo[f,h]benzothieno[2,3‐c]‐quinolin‐10(9H)‐one ( 4 ) and dibenzo[f,h]naphtho[2′,1′:4,5]thieno[2,3‐c]quinolin‐10(9H)‐one ( 11 ), respectively. Further elaboration of the lactams provided three novel unsubstituted new ring systems.     

Synthesis of C3 benzo[1,2-e:3,4-e':5,6-e"]tribenzo[l]acephenanthrylenes ("crushed fullerene" derivatives) by intramolecular palladium-catalyzed arylation

The C60 polyarenes 4, 5, 18 a, and 18 b have been synthesized from truxene by triple alkylation at C5, C10, and C15 followed by a palladium-catalyzed intramolecular arylation. The synthesis of "crushed fullerene" C60H30 (2) is the most efficient reported to date and proceeds in 33% overall yield.     

Nickel-catalyzed regioselective access to dibenzo[c,f]oxocine framework via reductive Heck reaction

Nickel-catalyzed regioselective construction of dibenzo[c,f]oxocine framework with tri-substituted exo-cyclic alkenes have been obtained through an efficient implementation of reductive-Heck protocol. This cost effective, efficient methodology has been demonstrated for the synthesis of various dibenzo[c,f]oxocine derivatives with moderate to good yields.     

Dihydrodiols and diol epoxides of dibenzo[a,i]-and [a,h]pyrene

Syntheses of dihydrodiols and highly mutagenic diol epoxides of the carcinogenic polycyclic aromatic hydrocarbons dibenzo[a,i]-and [a,h]pyrene are described.     

Synthesis,characterization, thermal, and optical properties of conjugated copolymers derived from phenanthrene-9,10-dione- and dibenzo[f,h]quinoxaline

Donor–acceptor (D-A) conjugated polymers bearing phenanthrene-9,10-dione and dibenzo[f,h]quinoxaline as the acceptor units were synthesized via an optimized Suzuki cross-coupling reaction. Each of the aforementioned acceptors was reacted with three different donor comonomers, namely, fluorene, carbazole, and silafluorene derivatives, bearing long alkyl chains. The resulting copolymers display excellent solubility in common organic solvents with high chemical stability, allowing for the determination of their structural, thermal, and optical properties by various analytical techniques.     

Synthesis,Characterization, and Catalytic Application of Palladium Complexes Containing Indolyl-NNN-Type Ligands

In this study, a series of N-heterocyclic indolyl ligand precursors 2-Py-Py-IndH, 2-Py-Pz-IndH, 2-Py-7-Py-IndH, 2-Py-7-Pz-IndH, and 2-Ox-7-Py-IndH (L¹H-L⁵H) were prepared. The treatment of ligand precursors with 1 equivalent of palladium acetate affords palladium complexes 1–5. All ligand precursors and palladium complexes were characterized by NMR spectroscopy and elemental analysis. The molecular structures of complexes 3 and 5 were determined by single crystal X-ray diffraction techniques. The application of those palladium complexes 1–5 to the Suzuki reaction with aryl halide substrates was examined.     

Synthesis of polyoxygenated dibenzo[a,e]cycloheptatrienes

A successive route for the synthesis of substituted dibenzo[a,e]cycloheptatriene 1 was established by the reduction of 2-allylbenzaldehyde 4, the BF₃·OEt₂-mediated intermolecular coupling of 2-allylphenylmethanol 5 with oxygenated benzenes 6, the olefinic oxidative cleavage of 7 and the intramolecular ring-closure of 8. Functionalized anthracene 13 were prepared from 2-vinylbenzaldehyde 9. The key structures were confirmed by X-ray single crystal diffraction analysis.     

One-step synthesis of some polyfluoroalkylated 1,3-benzodioxoles, 4H-1,3-benzodioxins and dibenzo[d,f] [1,3]dioxepins

Several polyfluoroalkylated heterocyclic compounds containing methylenedioxy group such as 2-(F-alkyl) substituted 1,3-benzodioxole, piperonal, 4H-1,3-benzodioxin, 1,3-dioxolane and 6-(F-alkyl) substituted dibenzo[d, f][1,3]dioxepin have been prepared through double Michael-addition reactions of 2,2-dihydropolyfluoroalkanoates with the corresponding diphenols or diols in high yields.     

螺[二苯并[a,j]氧杂蒽-14,9’-芴]的合成及性质简

芴酮与2-萘酚在硫酸和3-巯基丙酸的作用下反应得到化合物螺[二苯并[a,j]氧杂蒽-14,9’-芴]. 采用核磁共振、质谱、红外光谱和元素分析等对该化合物进行了表征,并通过X射线衍射法测得了其晶体结构,确定该化合物是通过二苯并[a,j]氧杂蒽中的含氧六元杂环和芴中的五元环共用一个碳原子形成一个螺环. 利用荧光光谱和热分析等手段对该化合物的性质进行了研究,结果表明其最大荧光发射峰为366 nm,熔点为297 ℃,热分解温度为329 ℃,具有较高的热稳定性.     

Synthesis, electrochemical and intramolecular charge-transfer properties of ‘calix[4]arene-acceptor’ diad and triad derivatives

Calix[4]arenes substituted with various acceptor moieties (naphthoquinone (NQ), tetracyanoanthraquinodimethane (TCNAQ)) have been synthesized. In these derivatives the three-dimensional structure of calix[4]arene acts as a weak electron donor (D), connected via a linear sigma spacer to one or two electroactive acceptor (A) units. The electrochemical behavior of these derivatives has been studied by cyclic voltammetry. The UV-Vis spectrum of the TCNAQ triad (A-D-A, 13) reveals the presence of a weak intramolecular charge transfer absorption band.     

Synthesis of unsymmetrical pincer CNN palladium complex of 8-dimethylamino-3-ferrocenylmethyl-3-azabicyclo[3.2.1]octane and its catalytic activity in the Suzuki reaction

New bicyclic unsymmetrical CNN palladium 5,6-membered pincer complex was synthesized from 3-ferrocenylmethyl-8-dimethylamino-3-azabicyclo[3.2.1]octane by its direct cyclo-palladation with Li₂PdCl₄ or Na₂PdCl₄ and sodium acetate in MeOH. The obtained complex exhibited high catalytic activity in the Suzuki cross-coupling between aryl bromides and phenylboronic acid.     

Synthesis and Theoretical Study of Intramolecular Hydrogen Bond at Two Possible Positions in Pyrazolo[1,2‐b]phthalazine

Properties of dimethyl 3‐(alkylamino)‐5,10‐dioxo‐5,10‐dihydro‐1H‐pyrazolo[1,2‐b]phthalazine‐1,2‐dicarboxylate and its derivatives were studied by means of ab initio method. NO₂ derivative of title compound was synthesized and the nature of its intramolecular hydrogen bond (HB) was investigated. Furthermore, the topological properties of the electron density distributions for N? H···O intramolecular bridges were analyzed in terms of the Bader theory of atoms in molecules (AIM). The electron density (ρ) and Laplacian (?²ρ) properties, estimated by AIM calculations, indicated that O···H bond possesses low ρ and positive ?²ρ values which are in agreement with electrostatic character of the HBs, whereas N? H bonds have covalent character (?²ρ<0). Moreover, steric effect of the t‐Bu group on structure and topological parameters of pyrazolo[1,2‐b]phthalazine conformers was studied. Finally, the powerful method of Espinosa was used to obtain the H‐bond energy.     

Synthesis,characterization and catalytic activity of new aminomethyldiphosphine–Pd(II) complexes for Suzuki cross‐coupling reaction

A new range of CF₃‐substituted aminomethyldiphosphine (P―C―N) ligands ((C₆H₅)₂PCH₂)₂NR (R = ―C₆H₄(2‐CF₃) ( 1 ), ―C₆H₄(3‐CF₃) ( 1b ) has been synthesized from 2‐(trifluoromethyl)aniline and 3‐(trifluoromethyl)aniline with diphenylphosphine. The aminomethyldiphosphine ligands were reacted with Pd(cod)Cl₂ to give corresponding metal complexes, PdLCl₂ ( 2a , 2b ). The aminomethyldiphosphine–palladium compounds were characterized by utilizing several methods including NMR (¹H, ¹³C, ³¹P) and elemental analysis. These compounds were used as catalysts in Suzuki cross‐coupling reaction of aryl chlorides and bromides. The effect of base was also investigated in this current project. CF₃‐substituted aminomethyldiphosphine–palladium complexes were found to be efficient catalysts in Suzuki cross‐coupling reaction of activated and deactivated aryl boronic acids. Copyright © 2013 John Wiley & Sons, Ltd.     

螺[二苯并[a,j]氧杂蒽-14,9'-芴]的合成及性质

芴酮与2-萘酚在硫酸和3-巯基丙酸的作用下反应得到化合物螺[二苯并[a,j]氧杂蒽-14,9'-芴]. 采用核磁共振、 质谱、 红外光谱和元素分析等对该化合物进行了表征, 并通过X射线衍射法测得了其晶体结构, 确定该化合物是通过二苯并[a,j]氧杂蒽中的含氧六元杂环和芴中的五元环共用一个碳原子形成一个螺环. 利用荧光光谱和热分析等手段对该化合物的性质进行了研究, 结果表明其最大荧光发射峰为366 nm, 熔点为297 ℃, 热分解温度为329 ℃, 具有较高的热稳定性.     

Synthesis of (‐)‐herbertenediol and (aR,aS)‐mastigophorenes A via asymmetric intramolecular heck coupling reaction

Total enantioselective synthesis of the natural (‐)‐Herbertenediol (1) was accomplished in eleven steps with an overall yield of 15% starting from the 2‐methoxy‐4‐methyl‐phenol. The total synthesis features asymmetric intramolecular Heck reaction and Wolff‐Kishner‐Huang reduction. (aR, aS)‐Mastigophorenes A was also synthesized through the oxidative coupling reaction.     

Dibenzo[b,f]oxepin‐10(11H)‐one and dibenzo[b,f]thiepin‐10(11H)‐one as useful synthons in the synthesis of various dibenzo[e,h]azulenes

The present review focuses on dibenzo[b,f]oxepin‐10(11H)‐one ( I , X = O) and dibenzo[b,f]thiepin‐10(11H)‐one ( I , X = S) as common synthons in the efficient synthesis of various dibenzoxepino[4,5‐ and dibenzothiepino[4,5]‐fused five‐membered heterocycles: [2,3] fused thiophene ( II ), [3,4] fused thiophene ( III ), furan ( IV ), pyrrole ( V ), imidazole ( VI ), pyrazole ( VII ), oxazole ( VIII ), and thiazole ( IX ). The potential of I to be converted into reactive intermediates that readily undergo heteroaromatic annulation reactions by cyclocondensation with proper binucleophiles allows formation of a range of enumerated functionalized dibenzo[e,h]azulene [4] structures ( II , III , IV , V , VI , VII , VIII , IX ). Dibenzo[e,h]azulenes as heterotetracyclic scaffold can be exploited in further modifications to obtain compounds with altered physicochemical and biological profile. J. Heterocyclic Chem., (2012).