- Efficient C-F and C-C activation by a novel N-heterocyclic carbene-nickel(0) complex
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The NHC-stabilized complex [Ni2(iPr2Im) 4(cod)] (1) was isolated in good yield from the reaction of [Ni-(cod)2] with 1,3-diisopropylimidazole-2-ylidene (iPr 2Im). Compound 1 is a source of the [Ni(iPr
- Schaub, Thomas,Radius, Udo
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Read Online
- A palladium catalyzed domino coupling process to substituted phenanthrenes
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A palladium catalyzed annulation reaction of diphenylacetylene with iodobenzene leads to 9,10-diphenylphenanthrene. The regiochemistry of this domino coupling process is studied, suggesting the cis-trans isomerization of vinyl palladium complexes as react
- Dyker, Gerald,Kellner, Andreas
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Read Online
- Exploring highly efficient light conversion agents for agricultural film based on aggregation induced emission effects
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Aggregation-induced emission (AIE) is a unique photo-physical phenomenon that has become an emerging and hot research area. It has a wide range of applications due to its excellent luminous properties. In this paper, five compounds and their corresponding light conversion films were prepared based on AIE effects and the thermally activated delayed fluorescence (TADF) phenomenon. Furthermore, ultraviolet conversion, dispersion and photo-physical properties such as UV-vis spectra, fluorescence spectra, and photo stability as well as the mechanical properties of the light conversion films were investigated in detail. The results reveal that triphenylacrylonitrile (TPA) exhibits excellent photo stability and ultraviolet light conversion properties. In addition, the fluorescence emission spectrum of TPA corresponds well with the absorption spectrum of plants in the blue-violet region. In particular, the light conversion film with added TPA also shows enhanced mechanical properties and slightly lower visible light transmittance (3.79%) compared to PVC blank film. Based on the photo stabilities of the five compounds, it can be concluded that the electron-withdrawing cyano group can increase the photo stability of TPA, while carbazole substituents are proved to have an uncertain effect on the rate of photo oxidation, which is attributed to the electron-donating properties of carbazole and increased molecular distortion or rigidity. Finally, it is worth mentioning that this is the first report utilizing AIE-active luminogens (AIEgens) in agricultural light conversion film.
- Qi, Yunpeng,Wang, Yongtao,Yu, Yongjiang,Liu, Zhiyong,Zhang, Yan,Qi,Zhou, Changtong
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Read Online
- Mechanistic Study of Highly Efficient Direct 1,2-Carboboration of Alkynes with 9-Borafluorenes
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We recently reported a new one-pot transformation of alkynes into 9,10-diarylphenanthrene derivatives, which proceeds through efficient catalyst-free 1,2-carboboration of alkynes with 9-chloro-9-borafluorene (1Cl), which yields a chlorodibenzoborepin, followed by oxidative deborylation/C?C coupling of the resultant chlorodibenzoborepin. Herein, based on new experimental observations for the catalyst-free 1,2-carboboration by using diphenylacetylenes and 1Br or 1OTf as well as results from theoretical investigations, we show how the substituent on the boron atom of 9-borafluorene affects the reactivity toward alkynes. Kinetic studies indicated that the 1,2-carboboration of diphenylacetylene with the borafluorenes can be described as a second-order reaction. The reaction rates became larger with the increase in the acceptor numbers of the borafluorenes (1Br>1OTf>1Cl), which was evaluated by the Gutmann–Beckett method based on a Lewis acid/base complexation in solution. Interestingly, thermodynamic parameters obtained experimentally indicated that the term of activation entropy, rather than the term of activation enthalpy, largely contributes to the reaction rate. This experimental result was also supported by DFT calculations. Overall, among the borafluorenes examined, 1Br exhibited the highest reactivity toward a wide variety of substituted diarylacetylenes. Similar to the case of chlorodibenzoborepin, when the dibenzoborepin obtained from 1Br or 1OTf was oxidized by using FeCl3, an efficient deborylation/C?C coupling took place to give the corresponding 9,10-diarylphenanthrene derivatives in high yields.
- Shoji, Yoshiaki,Shigeno, Naoki,Takenouchi, Kumiko,Sugimoto, Manabu,Fukushima, Takanori
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Read Online
- Fluorescent self-assembled nanowires of AIE fluorogens
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The self-assembly of fluorescent molecules is of general interest due to the potential fabrication of nanostructured materials. The fabrication of fluorescent nanowires remains challenging because the inherent aggregation in the self-assembly process quen
- Hu, Rongrong,Lam, Jacky W. Y.,Deng, Haiqin,Song, Zhegang,Zheng, Chao,Tang, Ben Zhong
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Read Online
- Quantitative application of principal component analysis and self-modeling spectral resolution to product analysis of tetraphenylethylene photochemical reactions
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Tetraphenylethylene readily undergoes photochemical reactions in room-temperature solutions. Principal component analysis and self-modeling spectral resolution are applied to the characterization of reaction products. On the basis of principal component a
- Bunker, Christopher E.,Hamilton, Norwood B.,Sun, Ya-Ping
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Read Online
- α-Bromoacrylic Acids as C1 Insertion Units for Palladium-Catalyzed Decarboxylative Synthesis of Diverse Dibenzofulvenes
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Herein α-bromoacrylic acids have been employed as C1 insertion units to achieve the palladium-catalyzed [4 + 1] annulation of 2-iodobiphenyls, which provides an efficient platform for the construction of diverse dibenzofulvenes. This protocol enables the formation of double C(aryl)-C(vinyl) bonds via a C(vinyl)-Br bond cleavage and decarboxylation. It is particularly noteworthy that the method features a broad substrate scope, and various interesting frameworks, such as bridged ring, fused (hetero)aromatic ring, and divinylbenzene, can be successfully incorporated into the products.
- Zhang, Minghao,Deng, Wenbo,Sun, Mingjie,Zhou, Liwei,Deng, Guobo,Liang, Yun,Yang, Yuan
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p. 5744 - 5749
(2021/08/18)
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- Aromatic Metamorphosis of Thiophenes by Means of Desulfurative Dilithiation
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A new mode of aromatic metamorphosis has been developed, which allows thiophenes and their benzo-fused derivatives to be converted to a variety of exotic heteroles. This transformation involves 1) the efficient generation of key 1,4-dianions by means of desulfurative dilithiation with lithium powder and 2) the subsequent trapping of the dianions with heteroatom electrophiles in a one-pot manner. Via the desulfurative dilithiation, the sulfur atoms of thiophenes are replaced also with a carbon–carbon double bond or a 1,2-phenylene for the construction of benzene rings.
- Kaga, Atsushi,Iida, Hirokazu,Tsuchiya, Shun,Saito, Hayate,Nakano, Koji,Yorimitsu, Hideki
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supporting information
p. 4567 - 4572
(2021/02/12)
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- Synthesis of Phenanthrenes via Palladium-Catalyzed Three-Component Domino Reaction of Aryl Iodides, Internal Alkynes, and o-Bromobenzoic Acids
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A new palladium-catalyzed domino alkyne insertion/C-H activation/decarboxylation sequence has been developed, which provides an efficient approach for synthesizing a variety of functionalized phenanthrenes in moderate to good yields. The method shows broad substrate scope and good functional group tolerance by employing readily available materials, including aryl iodides, internal alkynes, and o-bromobenzoic acids, as three-component coupling partners.
- Deng, Guobo,Liang, Yun,Luo, Xiai,Yang, Xiumei,Yang, Yuan,Yang, Yuzhong,Zhou, Liwei
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p. 1223 - 1230
(2020/04/15)
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- A Theoretical Study on the Mechanism of the Oxidative Deborylation/C-C Coupling Reaction of Borepin Derivatives
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One-electron oxidation of borepin derivatives that consists of a boron-containing seven-membered ring has been reported to cause deborylation/C-C coupling, yielding aromatic compounds. The reaction can be achieved not only by transition metal compounds but also by oxidants without transition metal such as O2 and other organic compounds. Despite numerous experimental attempts, the mechanism of this peculiar reaction as well as the fate of the BCl part eliminated from borepin remain unclear to date. Based on theoretical approaches using the artificial force induced reaction method, here we address the mechanism of the unusual boron-mediated C-C coupling. For this purpose, two borepin derivatives (1 and 35), bearing ethyl and phenyl groups, respectively, were used as reactants, and FeCl3/MeNO2 and O2 were chosen as oxidants. The calculations revealed reaction pathways that provided an overall picture of the mechanism of the target reaction, which features four key steps, namely, (i) quaternization of the boron atom by the coordination of oxidant, (ii) intersystem crossing, (iii) skeletal rearrangement to form a six-membered ring, and (iv) elimination of a boron moiety. The intrinsic nature of boron, i.e., a strong tendency to accept a coordination ligand even under oxidative conditions, is responsible for the oxidative deborylation/C-C coupling of borepin.
- ?zen, Cihan,Shoji, Yoshiaki,Fukushima, Takanori,Maeda, Satoshi
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p. 1941 - 1950
(2019/05/16)
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- A palladium-catalyzed multi-component annulation approach towards the synthesis of phenanthrenes
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An efficient palladium-catalyzed three-component cascade reaction has been developed for the facile construction of phenanthrene frameworks. The transformation is driven by a controlled reaction sequence of Suzuki-Miyaura coupling followed by the insertion of alkynes, and finally, annulation to yield phenanthrene derivatives via C-H activation. This methodology is able to accommodate a variety of substrates and affords the anticipated products in good to excellent yields.
- Song, Juan,Wang, Songjiang,Sun, Haisen,Fan, Yuxuan,Xiao, Kang,Qian, Yan
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supporting information
p. 3328 - 3332
(2019/04/01)
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- Base-catalyzed diborylation of alkynes: synthesis and applications of cis-1,2-bis(boryl)alkenes
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An efficient, transition-metal free, and practical approach to cis-bis(boryl)alkenes from various alkynes was disclosed in the presence of a catalytic amount of K2CO3 under mild conditions. Meanwhile, tetrasubstituted alkenes and phenanthrene derivatives were readily constructed from the target diborylalkenes via Suzuki-Miyaura cross coupling.
- Kuang, Zhijie,Gao, Guoliang,Song, Qiuling
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- Rhodaelectrocatalysis for Annulative C?H Activation: Polycyclic Aromatic Hydrocarbons through Versatile Double Electrocatalysis
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Rapid access to structurally diversified polycyclic aromatic hydrocarbons (PAHs) in a controlled manner is of key significance in materials sciences. Herein, we describe a strategy featuring two distinct electrocatalytic C?H transformations for the synthesis of novel nonplanar PAHs. The combination of rhodaelectrooxidative C?H activation/[2+2+2] alkyne annulation of easily accessible boronic acids with electrocatalytic cyclodehydrogenation provided modular access to diversely substituted PAHs with electricity as a sustainable oxidant. The unique molecular topology as well as the photophysical and electronic properties of the thus obtained PAHs were fully analyzed. The unique power of this metallaelectrocatalysis method was demonstrated by the chemoselective assembly of synthetically useful iodo-substituted PAHs.
- Kong, Wei-Jun,Finger, Lars H.,Oliveira, Jo?o C. A.,Ackermann, Lutz
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supporting information
p. 6342 - 6346
(2019/04/08)
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- Synthetic method of phenanthrene, and phenanthrene derivative
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The invention discloses a synthetic method of phenanthrene, and a phenanthrene derivative. The synthetic method comprises following steps: under nitrogen gas protection, in a toluene solution, an o-bromoiodobenzene compound, aryl boric acid, and a diaryl
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Paragraph 0062-0069
(2019/07/04)
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- Deciphering the working mechanism of aggregation-induced emission of tetraphenylethylene derivatives by ultrafast spectroscopy
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Aggregation-induced emission (AIE) is the long-sought solution to the problem of aggregation-caused quenching that has hampered efficient application of fluorescent organic materials. An important goal on the way to fully understand the working mechanism
- Cai, Yuanjing,Du, Lili,Samedov, Kerim,Gu, Xinggui,Qi, Fei,Sung, Herman H. Y.,Patrick, Brian O.,Yan, Zhiping,Jiang, Xiaofang,Zhang, Haoke,Lam, Jacky W. Y.,Williams, Ian D.,Lee Phillips, David,Qin, Anjun,Tang, Ben Zhong
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p. 4662 - 4670
(2018/05/30)
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- Palladium Catalyzed C-I and Vicinal C-H Dual Activation of Diaryliodonium Salts for Diarylations: Synthesis of Triphenylenes
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Using the synthetic strategy of palladium-catalyzed dual activation of both C-I and vicinal C-H bonds of diaryliodonium salts, we report an approach for direct diarylations of 2-bromobiphenyls or bromobenzenes. As a result, a wide range of triphenylenes with various substituents have been synthesized in good yields. These triphenylenes are expected to be employed in the "bottom-up" synthesis of functional aromatic molecules in material science.
- Wu, Xunshen,Han, Jianwei,Wang, Limin
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- π-CONJUGATED COMPOUND AND METHOD FOR PRODUCING THE SAME
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PROBLEM TO BE SOLVED: To provide π-conjugated compounds having various skeletons and a simple method for synthesizing the same and to provide a new π-conjugated compound. SOLUTION: There is provided a method for producing a π-conjugated compound which comprises a step of reacting a compound A and a compound B in the presence of an aprotic solvent, followed by subjecting the resulting borepin derivative to oxidation reaction. The compound A contains at least one of alkynyl groups directly bonded to a carbon atom and the compound B contains a unit in which a halogen atom (provided that a fluorine atom is excluded) or a trifluoromethanesulfonyl group and two aryl groups which may be bonded to each other to form a ring are directly bonded to boron. SELECTED DRAWING: None COPYRIGHT: (C)2017,JPOandINPIT
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Paragraph 0070; 0071
(2017/11/04)
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- Phenanthrene Synthesis by Palladium-Catalyzed Benzannulation with o-Bromobenzyl Alcohols through Multiple Carbon-Carbon Bond Formations
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A palladium-catalyzed benzannulation with o-bromobenzyl alcohols enabled the facile construction of phenanthrene skeletons via the sequential multiple carbon-carbon bond formations. A variety of multisubstituted phenanthrenes were synthesized by the reaction of (Z)-β-halostyrenes with o-bromobenzyl alcohols as well as by the three-component coupling of alkynes, aryl bromides, and o-bromobenzyl alcohols. The electron-deficient phosphine ligand played an important role to control the sequential oxidative addition of two different organic halides employed, which realized the selective formation of the desired phenanthrenes in good yields. This synthetic protocol was also applicable to the synthesis of the highly fused polycyclic aromatic hydrocarbons such as tetraphenes.
- Iwasaki, Masayuki,Araki, Yasuhiro,Nishihara, Yasushi
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p. 6242 - 6258
(2017/06/23)
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- One-Step Annulative π-Extension of Alkynes with Dibenzosiloles or Dibenzogermoles by Palladium/o-chloranil Catalysis
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Reliable and short synthetic routes to polycyclic aromatic hydrocarbons and nanographenes are important in materials science. Herein, we report an efficient one-step annulative π-extension reaction of alkynes that provides access to diarylphenanthrenes and related nanographene precursors. In the presence of a cationic palladium/o-chloranil catalyst system and dibenzosiloles or dibenzogermoles as π-extending agents, a variety of diarylacetylenes are transformed successfully into 9,10-diarylphenanthrenes in a single step with good functional-group tolerance. Furthermore, double π-extension reactions of 1,4-bis(phenylethynyl)benzene and diphenyl-1,3-butadiyne are demonstrated, affording oligoarylene products, which show potential for application in the synthesis of larger polycyclic aromatic hydrocarbons and nanographenes.
- Ozaki, Kyohei,Murai, Keiichiro,Matsuoka, Wataru,Kawasumi, Katsuaki,Ito, Hideto,Itami, Kenichiro
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supporting information
p. 1361 - 1364
(2017/01/24)
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- Phenanthrene Synthesis via Chromium-Catalyzed Annulation of 2-Biaryl Grignard Reagents and Alkynes
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A chromium/2,2′-bipyridine-catalyzed annulation reaction of 2-biarylmagnesium reagents with alkynes is reported. The reaction is applicable to a variety of aryl- and/or alkyl-substituted internal alkynes as well as 2-biaryl and related Grignard reagents, thus affording phenanthrene derivatives in moderate to good yields. The reaction proceeds at the expense of excess alkyne as a hydrogen acceptor and thus does not need an external oxidant. Deuterium-labeling experiments shed light on the reaction mechanism, which likely involves multiple intramolecular C-H activation processes on chromium.
- Yan, Jianming,Yoshikai, Naohiko
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supporting information
p. 6630 - 6633
(2017/12/26)
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- Synthesis of multiply substituted polycyclic aromatic hydrocarbons by iridium-catalyzed annulation of ring-fused benzocyclobutenol with alkyne through C-C bond cleavage
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The first iridium-catalyzed intermolecular cyclization between alkynes and ring-fused benzocyclobutenols (RBCB) through C-C bond cleavage is described. A variety of elusive polycyclic aromatic hydrocarbons (PAHs) with multiple substituents are obtained in good yields under mild conditions. This procedure provides a unique and expeditious tool for the synthesis of PAHs. Expanding the family: The iridium-catalyzed intermolecular cyclization between ring-fused benzocyclobutenols and alkynes through C-C bond cleavage is described. A variety of elusive polycyclic aromatic hydrocarbons (PAHs) with multiple substituents are obtained in good yields under mild conditions. The transformation exhibits good functional-group tolerance and regioselectivity.
- Yu, Jiajia,Yan, Hong,Zhu, Chen
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p. 1143 - 1146
(2016/01/20)
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- Rhodium-Catalyzed Oxidative Annulation of (2-Arylphenyl)boronic Acids with Alkynes: Selective Synthesis of Phenanthrene Derivatives
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A rhodium-catalyzed annulative coupling of (2-arylphenyl)boronic acids with alkynes has been developed for the facile construction of phenanthrene frameworks. The reaction proceeded without external bases, and dioxygen worked as a terminal oxidant. Deuter
- Nagata, Tomoya,Satoh, Tetsuya,Nishii, Yuji,Miura, Masahiro
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supporting information
p. 1707 - 1710
(2016/07/06)
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- Synthesis of Functionalized Phenanthrenes via Regioselective Oxidative Radical Cyclization
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The majority of Sn-mediated cyclizations are reductive and, thus, cannot give a fully conjugated product. This is a limitation in the application of Sn-mediated radical cascades for the preparation of fully conjugated molecules. In this work, we report an oxidatively terminated Bu3Sn-mediated cyclization of an alkyne where AIBN, the commonly used initiator, takes on a new function as an oxidative agent. Sn-mediated radical transformation of biphenyl aryl acetylenes into functionalized phenanthrenyl stannanes can be initiated via two potentially equilibrating vinyl radicals, one of which can be trapped by the fast 6-endoclosure at the biphenyl moiety in good to excellent yields. The efficient preparation of Sn-substituted phenanthrenes opens access to convenient building blocks for the construction of larger polyaromatics.
- Pati, Kamalkishore,Michas, Christopher,Allenger, David,Piskun, Ilya,Coutros, Peter S.,Dos Passos Gomes, Gabriel,Alabugin, Igor V.
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p. 11706 - 11717
(2015/12/11)
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- Synthesis of Multisubstituted Triphenylenes and Phenanthrenes by Cascade Reaction of o-Iodobiphenyls or (Z)-β-Halostyrenes with o-Bromobenzyl Alcohols through Two Sequential C-C Bond Formations Catalyzed by a Palladium Complex
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o-Bromobenzyl alcohol has been developed as a novel annulating reagent, bearing both nucleophilic and electrophilic substituents, for the facile synthesis of polycyclic aromatic hydrocarbons. A palladium/electron-deficient phosphine catalyst efficiently coupled o-iodobiphenyls or (Z)-β-halostyrenes with o-bromobenzyl alcohols to afford triphenylenes and phenanthrenes, respectively. The present cascade reaction proceeded through deacetonative cross-coupling and sequential intramolecular cyclization. An array of experimental data suggest that the reaction mechanism involves the equilibrium of 1,4-palladium migration.
- Iwasaki, Masayuki,Araki, Yasuhiro,Iino, Shohei,Nishihara, Yasushi
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p. 9247 - 9263
(2015/09/28)
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- Pd catalyzed insertion of alkynes into cyclic diaryliodoniums: A direct access to multi-substituted phenanthrenes
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Cyclic diaryliodoniums remain unexplored compared to linear iodoniums. In our current work, internal alkynes were for the first time applied to react with cyclic iodoniums, catalyzed by Pd, resulting in a [4 + 2] benzannulation. Our work offers a new strategy to synthesize multi-substituted phenanthrene derivatives which are not easily accessed by conventional methods.
- Wu, Yongcheng,Wu, Fuhai,Zhu, Daqian,Luo, Bingling,Wang, Haiwen,Hu, Yumin,Wen, Shijun,Huang, Peng
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p. 10386 - 10391
(2015/10/28)
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- Palladium-Catalyzed Annulation of 2,2 ′ -Dibromobiphenyls with Alkynes: Synthesis of Functionalized Phenanthrenes and Dibenzochrysenes
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A palladium-catalyzed annulation process of 2,2′-dibromobiphenyls with alkynes for the synthesis of functionalized phenanthrenes has been realized. The methodology provides an efficient approach to dibenzochrysene derivatives starting from simple reactants in two steps.
- Ma, Jun,Li, Gaoqiang,Qiao, Yan,Tu, Jingxuan,Liu, Sha,Xu, Feng
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p. 1991 - 1996
(2015/09/01)
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- KOt-Bu/DMF promoted intramolecular cyclization of 1,1′-biphenyl aldehydes and ketones: An efficient synthesis of phenanthrenes
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A new synthesis of phenanthrene derivatives has been achieved through intramolecular cyclization of 1,1′-biphenyl aldehydes and ketones promoted by KOt-Bu/DMF. A free radical reaction pathway is proposed.
- Chen, Yan-Yan,Zhang, Niu-Niu,Ye, Lin-Miao,Chen, Jia-Hua,Sun, Xiang,Zhang, Xue-Jing,Yan, Ming
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p. 48046 - 48049
(2015/06/16)
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- Iridium-catalyzed annulative coupling of 2-arylbenzoyl chlorides with alkynes: Selective formation of phenanthrene derivatives
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2-Arylbenzoyl chlorides undergo annulative coupling with internal alkynes in the presence of a catalyst system of [IrCl(cod)]2/P(t-Bu)3 to selectively afford the corresponding phenanthrene derivatives accompanied by elimination of carbon monoxide and hydrogen chloride. The reaction occurs without addition of any external base. Deuterium-labeling experiments using 2-(d5-phenyl)benzoyl chloride suggest that the rate-determining step does not involve the C2′-H bond cleavage. Formation of a [(t-Bu)3PH][(biphenyl-2,2′-diyl)Ir(CO)Cl2] complex dimer, of which the structure was determined by single-crystal X-ray analysis, from a stoichiometric reaction at 60 °C without addition of alkyne also supports the facile C-H cleavage.
- Nagata, Tomoya,Hirano, Koji,Satoh, Tetsuya,Miura, Masahiro
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p. 8960 - 8967
(2015/02/19)
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- Three-bond breaking of cyclic anhydrides: Easy access to polyfunctionalized naphthalenes and phenanthrenes
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Benzannulation of phthalic anhydrides with alkynes to polyfunctionalized naphthalenes and phenanthrenes was confirmed to be straightforward using a palladium catalytic system. Sequential liberation of CO2 and CO occurred via oxidative decomposition of anhydride. In the case of 1,8-naphthalenedicarboxylic anhydrides, both aryls were encompassed in the annulation reaction to afford acenaphthylenes.
- Jafarpour, Farnaz,Hazrati, Hamideh,Nouraldinmousa, Sorour
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supporting information
p. 3816 - 3819
(2013/09/02)
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- Remarkable catalytic property of nanoporous gold on activation of diborons for direct diboration of alkynes
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A novel catalytic property of nanoporous gold for activation of bis(pinacolato)diboron has been reported that allows the direct diboration of alkynes to proceed sufficiently in a heterogeneous process. The experimental results revealed that the nanoporous gold catalyst is able to cleave the B-B bond of bis(pinacolato)diboron without using any additives.
- Chen, Qiang,Zhao, Jian,Ishikawa, Yoshifumi,Asao, Naoki,Yamamoto, Yoshinori,Jin, Tienan
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p. 5766 - 5769
(2013/12/04)
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- Synthesis of diarylated aromatic hydrocarbons by dehydroxylation of diols using the titanium(IV) chloride and triethylamine reagent system
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1,2-Diarylacenaphthylene, 9,10-diarylphenanthrene and 9,10-diarylanthracene derivatives were obtained in good yields (61-92%) in short reaction times (5-30 min) from the corresponding diols with the titanium(III) reagent prepared in situ using the TiCl4/Et3N reagent system in dichloromethane at 25 °C. Georg Thieme Verlag Stuttgart ? New York.
- Periasamy, Mariappan,Beesu, Mallesh,Shanmugaraja, Masilamani
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p. 2913 - 2918
(2013/10/22)
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- Optical properties and photo-oxidation of tetraphenylethene-based fluorophores
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We report the optical properties of tetraphenylethene (TPE) and other TPE derivatives functionalised with an octyl group (TPE-OCT) and polyethyleneglycol group (TPE-PEG) in the side chain. We compared TPE-OCT and TPE-PEG with TPE in both organic solvents and under aqueous conditions. All materials exhibit aggregation-induced emission, however, uncommonly, TPE-PEG seems to aggregate in aqueous solution with enhanced photoluminescence quantum efficiency (PLQE) relative to that in organic solvents. All three materials can be photo-oxidised in solution to their diphenylphenanthrene derivative by irradiation with UV light (at both ≈1 and ≈5 mW cm-2), with a subsequent enhancement in PL efficiency. The electron-donating ether group increases the rate of oxidation relative to bare TPE and also photo-oxidation was shown to be solvent and concentration dependent. Finally, photo-oxidation was also demonstrated in the aggregate state.
- Aldred, Matthew P.,Li, Chong,Zhu, Ming-Qiang
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supporting information
p. 16037 - 16045
(2013/02/22)
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- Synthesis of aromatic compounds by catalytic C-C bond activation of biphenylene or angular [3]phenylene
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Substituted phenanthrenes and picenes were easily prepared by reaction of biphenylene or angular [3]phenylene with various alkynes in the presence of a catalytic amount of [IrCl(cod)]2/dppe (cod=1,5-cyclooctadiene, dppe=1,2-bis(diphenylphosphin
- Korotvicka, Ales,Cisarova, Ivana,Roithova, Jana,Kotora, Martin
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supporting information; experimental part
p. 4200 - 4207
(2012/05/07)
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- Sequential oxidative transformation of tetraarylethylenes to 9,10-diarylphenanthrenes and dibenzo[g, p]chrysenes using DDQ as an oxidant
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Tetraarylethylenes can be sequentially transformed into 9,10-diarylphenanthrenes and dibenzo[g,p]chrysenes using 1 and 2 equiv of DDQ, respectively, in CH2Cl2 containing methanesulfonic acid, in excellent yields. Efficient access to substituted dibenzochrysenes from tetraarylethylenes establishes the versatility of this procedure over the existing multistep syntheses of dibenzochrysenes. Moreover, the ready regeneration of DDQ from easily recovered reduced DDQ-H2 continues to advance the use of DDQ/H+ for the oxidative C-C bond forming reactions.
- Navale, Tushar S.,Thakur, Khushabu,Rathore, Rajendra
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supporting information; experimental part
p. 1634 - 1637
(2011/05/06)
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- Phenanthrene synthesis by iron-catalyzed [4 + 2] benzannulation between alkyne and biaryl or 2-alkenylphenyl Grignard reagent
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The [4 + 2] benzannulation reaction of internal or terminal alkynes with 2-biaryl, 2-heteroarylphenyl, or 2-alkenylphenyl Grignard reagents in the presence of Fe(acac)3, 4,4′-di-tert-butyl-2,2′-bipyridyl, and 1,2-dichloro-2-methylpropane takes place at room temperature in 1 h to give 9-substituted or 9,10-disubstituted phenanthrenes and congeners in moderate to excellent yields. The reaction tolerates sensitive functional groups such as bromide and olefin. When applied to a 1,3-diyne, the annulation reaction takes place on both acetylenic moieties to give a bisphenanthrene derivative.
- Matsumoto, Arimasa,Ilies, Laurean,Nakamura, Eiichi
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supporting information; experimental part
p. 6557 - 6559
(2011/06/19)
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- Synthesis of highly substituted acenes through rhodium-catalyzed oxidative coupling of arylboron reagents with alkynes
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The rhodium-catalyzed oxidative 1:2 coupling reactions of arylboronic acids or their esters with alkynes smoothly proceed to produce the corresponding annulated products. Of special note, highly substituted, readily soluble, and tractable anthracene and tetracene derivatives can be obtained selectively from 2-naphthyl- and 2-anthrylboron reagents, respectively.
- Fukutani, Tatsuya,Hirano, Koji,Satoh, Tetsuya,Miura, Masahiro
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experimental part
p. 2867 - 2874
(2011/05/28)
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- Palladium-catalyzed double cross-coupling reaction of 1,2- bis(pinacolatoboryl)alkenes and -arenes with 2,2′-dibromobiaryls: Annulative approach to functionalized polycyclic aromatic hydrocarbons
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This study demonstrates that the double cross-coupling reaction of 1,2-bis(pinacolatoboryl)alkenes and -arenes with 2,2′-dibromobiaryls proceeds smoothly with the aid of a catalytic amount of Pd(PPh3) 4 in the presence of excess base to give a variety of polycyclic aromatic hydrocarbons, such as phenanthrenes, [5]helicene, dithienobenzenes, triphenylenes, dibenzo[g,p]chrysenes, and triphenyleno[1,2-b:4,3-b′] dithiophenes in good to high yields. It is noteworthy that the annulations using 2,2′-dibromooctafluorobiphenyl as an electrophile furnish the otherwise difficult to synthesize octafluorophenanthrenes and semi-fluorinated dibenzo[g,p]chrysenes in high yields.
- Shimizu, Masaki,Nagao, Ikuhiro,Tomioka, Yosuke,Kadowaki, Tsugumi,Hiyama, Tamejiro
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experimental part
p. 8014 - 8026
(2011/11/05)
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- Generation of benzyne from benzoic acid using C-H activation
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ortho C-H activation of benzoic acids with Pd(ii) generates an oxapalladacycle that can decarboxylate to produce a palladium-associated aryne. The arynes then undergo [2+2+2] trimerisation to afford triphenylenes.
- Cant, Alastair A.,Roberts, Lee,Greaney, Michael F.
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supporting information; experimental part
p. 8671 - 8673
(2011/01/03)
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- Synthesis and redox behavior of novel 9,10-diphenylphenanthrenes
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The synthesis and electrochemical investigations of 9,10- diphenylphenanthrene 2a and its derivatives 2b-2e are reported. The cyclic voltammetry of derivatives 2a-2c and 2e in different solvent/Bu 4NPF6 electrolyte systems reveals th
- Schreivogel, Alina,Sieger, Monika,Baro, Angelika,Laschat, Sabine
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experimental part
p. 1912 - 1924
(2010/12/25)
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- Palladium-catalyzed intermolecular decarboxylative coupling of 2-phenylbenzoic acids with alkynes via C-H and C-C bond activation
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A novel protocol for palladium-catalyzed intermolecular formal [4 + 2] annulation of 2-phenylbenzoic acids with alkynes is described. Acridine is shown to be essential for the high reaction efficiency. Phenanthrene derivatives are formed in moderate to good yields without coupling (pseudo)halides or organometallic species.
- Wang, Congyang,Rakshit, Souvik,Glorius, Frank
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supporting information; experimental part
p. 14006 - 14008
(2010/12/24)
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- One-pot synthesis of diarylmethylidenefluorenes and phenanthrenes by palladium-catalyzed multiple C-H bond functionalization
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Chemical equation presented A palladium-catalyzed rapid synthesis of diarylmethylidenefluorenes and phenanthrenes by multiple C-H bond activation, C-C bond formation, and Heck-type cyclization is described (see scheme).
- Thirunavukkarasu, Vedhagiri S.,Parthasarathy, Kanniyappan,Cheng, Chien-Hong
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scheme or table
p. 1436 - 1440
(2010/06/15)
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- Synthesis of fluorenes via the palladium-catalyzed 5-exo-dig annulation of o-alkynylbiaryls
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The direct palladium-catalyzed intramolecular hydro arylation of o-alkynylbiaryls proceeded in a highly stereoselective manner producing fluorenes 2, the products of 5-exo-dig cyclization, in excellent yields. The cascade intermolecular arylation, incorpo
- Chernyak, Natalia,Gevorgyan, Vladimir
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scheme or table
p. 1101 - 1114
(2009/12/07)
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- Palladium-catalyzed annulation of vic-bis(pinacolatoboryl)alkenes and -phenanthrenes with 2,2′-dibromobiaryls: Facile synthesis of functionalized phenanthrenes and dibenzo[g,p]chrysenes
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(Chemical Equation Presented) Double-cross: An annulation approach to functionalized polycyclic aromatic hydrocarbons involving a palladium-catalyzed double cross-coupling reaction of vic-diborylalkenes and -phenanthrenes with 2,2′-dibromobiaryls led to a variety of phenanthrenes and dibenzo-[g,p]chrysenes, as well as [5]helicenes, dithienobenzenes, and triphenyleno[1,2-b:4,3-b′]dithiophenes (see scheme; Bpin = pinacolatoboryl).
- Shimizu, Masaki,Nagao, Ikuhiro,Tomioka, Yosuke,Hiyama, Tamejiro
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supporting information; experimental part
p. 8096 - 8099
(2009/04/12)
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- Salt/ligand-activated low-valent titanium formulations: the 'salt effect' on diastereoselective carbon-carbon bond forming SET reactions
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A comprehensive study on the influence of exogenously added electropositive metal salts as promoters/secondary activators on preformed LVT species has resulted in the construction of highly efficient low-valent titanium (LVT) reagents. These salt-activated LVT reagents while exhibiting enhanced chemoselectivity and diastereoselectivity accelerated the reductive olefination rates of aromatic and aliphatic carbonyls under ambient temperature conditions and in much reduced reaction times. The versatility of the salted reagent was further explored in other single electron transfer reactions, namely, imino-pinacol couplings and one-pot synthesis of phenanthrenes from o-alkoxy aromatic carbonyls. We envisage that, in contrast to multiphase heterogeneous colloidal slurries, salt-activated LVT reagents afforded uniformly viscous homogeneous slurries generating a highly reactive monomeric intermetallic LVT complex. Continued judicious exploration of the emerging paradigms by studying the influence of external ligands/auxiliaries/redox agents on LVT reagents, and organometallics in general, will be critical to widen the scope and utility of the classical McMurry reaction and other SET reactions.
- Rele, Shyam M.,Nayak, Sandip K.,Chattopadhyay, Subrata
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p. 7225 - 7233
(2008/12/20)
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- Highly efficient route to fused polycyclic aromatics via palladium-catalyzed aryne annulation by aryl halides
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Polycyclic aromatic and heteroaromatic hydrocarbons have been synthesized in high yield by two different processes involving the Pd-catalyzed annulation of arynes. The first process involves a Pd-catalyzed annulation of arynes by 2-halobiaryls and related vinylic halides. The second process utilizes a Pd-catalyzed double annulation of arynes by simple aryl halides. Both processes appear to involve the catalytic, stepwise coupling of two very reactive substrates, an aryne and an organopalladium species, to generate excellent yields of cross-coupled products.
- Liu, Zhijian,Larock, Richard C.
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p. 223 - 232
(2007/10/03)
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- Photochemical electron-transfer generation of arylthiirane radical cations with tetranitromethane and chloranil - Some novel observations
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The radical cations from 2,2,3,3-tetraphenylthiirane (1a), 2,2-bis(4-methoxyphenyl)-3,3-diphenylthiirane (1b), and trans-2,3- diphenylthiirane (1c) have been generated by photoinduced electron transfer (PET) reactions with tetranitromethane [C(NO2)4] and chloranil (CA). A charge-transfer complexe (CTC) absorption is observed by UV/Vis spectroscopy between thiiranes (1) and C(NO2)4. On the other hand, quenching studies with azulene suggest that the ET reaction occurs between thiiranes and the triplet CA (3CA). The photochemical reaction of the CTC between thiiranes 1 and C(NO2)4 yields mainly the corresponding alkenes from the fragmentation of the radical-cation intermediate 1.+, together with the products derived from nitration on the phenyl rings. However, oxygen transfer to afford the sulfoxides is not found. A marked solvent effect is observed in this reaction, with cage coupling favored in CH2Cl2 (nitration derivatives as primary products) and non-cage coupling observed in CH3CN (the alkene as the primary product). The PET reactions between 1a-b and CA, in the presence of CH3OH (or another possible oxygen-centered nucleophile), give the ketone derivatives through ring opening, followed by oxidative cleavage. Conversely, under the same experimental conditions, the thiirane 1c affords only trans-stilbene 2c. This different behavior is ascribed to a different spin density in the corresponding singly occupied molecular orbital (SOMO) of the radical cation. For 1c+., the spin density is concentrated at the sulfur atom, whereas for 1a.+ and 1b.+, the charge is distributed onto the aromatic rings. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
- Puiatti, Marcelo,Argueello, Juan E.,Penenory, Alicia B.
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p. 4528 - 4536
(2007/10/03)
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- Generation of benzocyclobutadiene derivatives from zirconaindene derivatives
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Zirconaindene derivatives produced benzocyclobutadiene derivatives in situ in the presence of CuCl and 1,4-naphthoquinone, which afforded their dimers, 6a, 10b-dihydrobenzo[a]biphenylenes and dibenzosemibullvalenes or dibenzo[a,e]-cycloctenes.
- Chen, Chao,Xi, Chanjuan,Liu, Yuanyuan,Hong, Xiaoyin
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p. 5373 - 5376
(2007/10/03)
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- BF3·2CF3CH2OH (BF 3·2TFE), an efficient superacidic catalyst for some organic synthetic transformations
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BF3 · 2CF3CH2OH complex was found to be a very effective superacidic catalyst comparable in acid strength to at least that of 100% anhydrous sulfuric acid for various acid-catalyzed organic transformations such as isomerizations, rearrangements, ionic hydrogenation of various ketones, and aromatics with triethylsilane and nitration of aromatics with metal nitrate. Studies of the pivalaldehyde-methyl isopropyl ketone rearrangement and the benzopinacol to phenanthrene transformation suggest that the complex has an acidity comparable to that of 100% anhydrous sulfuric acid. The structure and properties of the 1:2 boron trifluoride-trifluoroethanol complex have been further studied using NMR (1H, 13C, 19F, 11B) and DFT calculations at the B3LYP/6- 311++G**//B3LYP/6-31G* level.
- Prakash, G. K. Surya,Mathew, Thomas,Marinez, Eric R.,Esteves, Pierre M.,Rasul, Golam,Olah, George A.
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p. 3952 - 3958
(2007/10/03)
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- Chromium-mediated synthesis of polycyclic aromatic compounds from halobiaryls
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(Chemical Equation Presented) Reaction of 2,2′-dihalobiphenyl with butyllithium followed by the addition of chromium(III) chloride and alkynes afforded the corresponding phenanthrene derivatives via formal [4 + 2] cycloaddition. A variety of alkynes could be used for this reaction, such as alkyl, aryl, silyl, and alkoxycarbonyl alkynes. Repetitive process of the reaction gave more extended polycyclic compounds such as benzo[g]chrysene and azacyclopentaphenalene derivatives.
- Kanno, Ken-Ichiro,Liu, Yuanhong,Iesato, Atsushi,Nakajima, Kiyohiko,Takahashi, Tamotsu
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p. 5453 - 5456
(2007/10/03)
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- Synthesis of 9-alkylidene-9H-fluorenes by a novel, palladium-catalyzed cascade reaction of aryl halides and 1-aryl-1-alkynes
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In the presence of a palladium catalyst and NaOAc, aryl iodides react with 1-aryl-1-alkynes to afford 9-alkylidene-9H-fluorenes in good yields. The products from this reaction are highly dependent on the base employed. This process appears to involve (1)
- Larock,Tian
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p. 7372 - 7379
(2007/10/03)
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- Synthesis of 9-alkylidene-9H-fluorenes by a novel palladium-catalyzed rearrangement
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(matrix presented) In the presence of a palladium catalyst and NaOAc, aryl iodides react with 1-aryl-1-alkynes to afford 9-alkylidene-9H-fluorenes in good yields. This process appears to involve (1) oxidative addition of the aryl iodide to Pd(0), (2) alkyne insertion, (3) rearrangement of the resulting vinylic palladium intermediate to an arylpalladium species, and (4) aryl-aryl coupling with simultaneous regeneration of the Pd(0) catalyst.
- Tian, Qingping,Larock, Richard C.
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p. 3329 - 3332
(2007/10/03)
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