Chemistry – An Asian Journal

Cover image for Vol. 8 Issue 5

May 2013

Volume 8, Issue 5

Pages 837–1041

  1. Cover Pictures

    1. Top of page
    2. Cover Pictures
    3. Graphical Abstract
    4. News
    5. Focus Review
    6. Communications
    7. Full Papers
    1. You have free access to this content
      Cover Picture: Surface-Initiated, Reversible Polymerization from Surface-Tethered Oligonucleotides by Enzymatic Processes (Chem. Asian J. 5/2013) (page 837)

      Prof. Dr. Jungkyu K. Lee, Mi Rae Kim, Prof. Dr. Insung S. Choi, Prof. Dr. Yang-Gyun Kim and Prof. Dr. Young Hwan Jung

      Article first published online: 23 APR 2013 | DOI: 10.1002/asia.201390012

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      Reversible polymerization has a great potential for the generation of reusable nanomaterials and complete repair of cracks or breaks in self-healing materials. In their Communication on page 908 ff., Young Hwan Jung et al. report on a surface-initiated, reversible polymerization of DNA that is processed by enzymatic reactions. Elongation of DNA, catalyzed by Taq DNA polymerase, is performed from a self-priming oligodeoxynucleotide anchored onto gold, and reversible de-polymerization and re-polymerization are achieved in a sequence-specific manner by using a restriction enzyme and Taq DNA polymerase. The cover picture was designed by Juno Lee.

    2. You have free access to this content
      Inside Cover: Surface-Passivated SBA-15-Supported Gold Nanoparticles: Highly Improved Catalytic Activity and Selectivity toward Hydrophobic Substrates (Chem. Asian J. 5/2013) (page 838)

      Dr. Jinsuo Gao, Xueying Zhang, Yan Yang, Jun Ke, Prof. Xinyong Li, Prof. Yaobin Zhang, Prof. Feng Tan, Prof. Jingwen Chen and Prof. Xie Quan

      Article first published online: 23 APR 2013 | DOI: 10.1002/asia.201390013

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      Surface-passivated SBA-15-supported gold nanoparticles that were nearly superhydrophobic, with a contact angle of 144°, were prepared by surface passivation based on a modified impregnation method, as reported by Jinsuo Gao et al. in their Full paper on page 934 ff. In their study, which is featured on the Inside Cover, the authors found that the catalytic activity of these nanoparticles regarding the reduction of nitrobenzene was significantly increased (>14 times) when compared with non-passivated SBA-15. Interestingly, the catalyst exhibited almost no catalytic activity for the more hydrophilic substrate 4-nitrophenol. Accordingly, such surface-passivated catalysts may find use in the selective catalysis of hydrophobic substrates.

  2. Graphical Abstract

    1. Top of page
    2. Cover Pictures
    3. Graphical Abstract
    4. News
    5. Focus Review
    6. Communications
    7. Full Papers
  3. News

    1. Top of page
    2. Cover Pictures
    3. Graphical Abstract
    4. News
    5. Focus Review
    6. Communications
    7. Full Papers
  4. Focus Review

    1. Top of page
    2. Cover Pictures
    3. Graphical Abstract
    4. News
    5. Focus Review
    6. Communications
    7. Full Papers
    1. Sensors

      Luminescent Noble Metal Nanoclusters as an Emerging Optical Probe for Sensor Development (pages 858–871)

      Xun Yuan, Zhentao Luo, Yong Yu, Qiaofeng Yao and Jianping Xie

      Article first published online: 19 MAR 2013 | DOI: 10.1002/asia.201201236

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      A noble bunch: Highly luminescent noble metal nanoclusters have recently emerged as promising probes for constructing high-performance optical sensors. This review summarizes the common syntheses and the luminescence properties of water-soluble luminescent thiolate- and protein-protected gold and silver nanoclusters and discusses the recent progress in their use as optical sensors with an emphasis on the underlying signal-generation mechanisms.

  5. Communications

    1. Top of page
    2. Cover Pictures
    3. Graphical Abstract
    4. News
    5. Focus Review
    6. Communications
    7. Full Papers
    1. Asymmetric Mannich-Type Reactions

      Chiral Calcium Iodide for Asymmetric Mannich-type Reactions of Malonates with Imines Providing β-Aminocarbonyl Compounds (pages 872–876)

      Dr. Tetsu Tsubogo, Shota Shimizu and Prof. Dr. Shū Kobayashi

      Article first published online: 11 MAR 2013 | DOI: 10.1002/asia.201300102

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      Out of the pybox: We have developed a novel chiral calcium iodide catalyst from CaI2 and a pybox that is stable under moisture and oxygen. This catalyst was applied to catalytic asymmetric Mannich-type reactions of malonates with both N-Boc-protected aromatic and aliphatic imines, and resulted in moderate to high yields with high enantioselectivities. To the best of our knowledge, this is the first example of highly enantioselective metal-catalyzed asymmetric Mannich-type reactions of malonates with N-Boc-protected aliphatic imines. The Mannich adduct was successfully converted into the α-hydroxy β-amino acid derivative. We have also shown the unique structure of the chiral Ca complexes with malonates.

    2. Solvent Effects

      A Catalyst-Free, One-Pot Three-Component Aminomethylation of α-Substituted Nitroacetates: Theoretical and Experimental Studies into the Rate-Accelerating Effects of the Solvent Methanol (pages 877–882)

      Cong-Bin Ji, Zhong-Yan Cao, Prof. Dr. Xin Wang, Prof. Dr. De-Yin Wu and Prof. Dr. Jian Zhou

      Article first published online: 5 MAR 2013 | DOI: 10.1002/asia.201300053

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      3, 2, 1 go! An unprecedented one-pot, catalyst-free, three-component aminomethylation of α-substituted nitroacetates, formalin, and amines has been reported, thereby enabling the highly efficient synthesis of α,β-diamino acid precursors with great structural diversity.

    3. Domino Reactions

      Cascade Oxidative Dearomatization/Semipinacol Rearrangement: An Approach to 2-Spirocyclo-3-oxindole Derivatives (pages 883–887)

      Jin-Bao Peng, Yue Qi, Ai-Jun Ma, Prof. Dr. Yong-Qiang Tu, Fu-Min Zhang, Shao-Hua Wang and Shu-Yu Zhang

      Article first published online: 19 FEB 2013 | DOI: 10.1002/asia.201300032

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      A novel cascade reaction involving oxidative dearomatization/semipinacol rearrangement of indol-2-yl cyclobutanols is explored with N-sulfonyloxaziridine (Davis oxaziridines) as oxidant, generating various 2-spiroquaternary 3-oxindoles in modest to good yields. This method might be useful in the synthesis of indole-based alkaloids bearing 2-spiroquaternary carbon centers. PTS=p-toluenesulfonic acid monohydrate.

    4. C[BOND]H Activation

      Redox Inactive Metal Ion Promoted C[BOND]H Activation of Benzene to Phenol with PdII(bpym): Demonstrating New Strategies in Catalyst Designs (pages 888–891)

      Huajun Guo, Zhuqi Chen, Fuming Mei, Dajian Zhu, Hui Xiong and Prof. Guochuan Yin

      Article first published online: 10 FEB 2013 | DOI: 10.1002/asia.201300003

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      Al in: A new strategy was introduced to modify the electronics and steric hindrance of the PdII ion in order to change its reactivity towards benzene hydroxylation. In trifluoroacetic acid, free PdII ions provide dominantly biphenyl, with phenol as minor product. Ligation of bpym to the PdII ion results in its deactivation with regard to benzene functionalization. The addition of the redox inactive AlIII ion to the PdII(bpym) complex recovers its catalytic activity, and alters the reactivity of PdII ion from benzene coupling to hydroxylation.

    5. Cyclization

      PtCl2-Catalyzed Tandem Enyne Cyclization/1,2 Ester Migration Reaction Controlled by Substituent Effects of All-Carbon 1,6-Enynyl Esters (pages 892–895)

      Xing Huo, Changgui Zhao, Gaoyuan Zhao, Shouchu Tang, Huilin Li, Dr. Xingang Xie and Prof. Dr. Xuegong She

      Article first published online: 20 FEB 2013 | DOI: 10.1002/asia.201300018

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      On the move: A novel PtCl2-catalyzed tandem 1,6-enyne cyclization/1,2-acyloxy migration reaction was developed, which was shown to be controlled by substitution effects. Using this method, a series of substituted enol esters containing the cyclopentenyl motif were prepared in moderate to high yields.

    6. Electrocatalysis

      Selective Electrochemical Recognition of the α-Naphthol Isomer and In Situ Immobilization of Naphthoquinones for Tunable Electrocatalysis (pages 896–901)

      Puchakayala Swetha and Prof. Annamalai Senthil Kumar

      Article first published online: 7 MAR 2013 | DOI: 10.1002/asia.201201170

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      Fits like a glove: Separationless and selective electrochemical oxidation of the α-naphthol (α-NAP) isomer yields naphthoquinone species on the surface of multiwalled carbon nanotubes, which can further catalyze the electro-oxidation of NADH and hydrazine at different potentials. The β-NAP isomer failed to show any such electro-oxidation.

    7. Mesoporous Materials

      Synthesis of Mesoporous Pt–Ru Alloy Particles with Uniform Sizes by Sophisticated Hard-Templating Method (pages 902–907)

      Prasannan Karthika, Hamed Ataee-Esfahani, Hongjing Wang, Malar Auxilia Francis, Hideki Abe, Natarajan Rajalakshmi, Kaveripatnam S. Dhathathreyan, Dakshinamoorthy Arivuoli and Yusuke Yamauchi

      Article first published online: 12 FEB 2013 | DOI: 10.1002/asia.201201107

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      Team work: Mesoporous Pt–Ru alloy particles with uniform sizes are synthesized by controlled chemical reduction with ascorbic acid using mesoporous silica as a hard template. Elemental mapping shows uniform distribution of Pt and Ru particles. The electrochemical activity and stability of the alloys towards methanol oxidation much higher than that of mesoporous Pt and commercial Pt catalyst.

    8. DNA Manipulation

      Surface-Initiated, Reversible Polymerization from Surface-Tethered Oligonucleotides by Enzymatic Processes (pages 908–911)

      Prof. Dr. Jungkyu K. Lee, Mi Rae Kim, Prof. Dr. Insung S. Choi, Prof. Dr. Yang-Gyun Kim and Prof. Dr. Young Hwan Jung

      Article first published online: 2 JAN 2013 | DOI: 10.1002/asia.201201092

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      Back and forth: Enzymatic, reversible polymerization on gold surfaces was efficiently carried out from surface-tethered self-priming oligodeoxynucleotides in a sequence-specific fashion by using two kinds of enzymes. Taq DNA polymerase, acting as a catalyst, facilitated DNA polymerization, and DNA restriction enzymes cut DNA polymers from the surface.

  6. Full Papers

    1. Top of page
    2. Cover Pictures
    3. Graphical Abstract
    4. News
    5. Focus Review
    6. Communications
    7. Full Papers
    1. Nanocrystals

      A Facile Phosphine-Free Method for Synthesizing PbSe Nanocrystals with Strong Optical Limiting Effects (pages 912–918)

      Tian-Ming Wang, Bao Gao, Dr. Qiang Wang, Min Zhao, Kai-Bin Kang, Prof. Zhu-Guo Xu and Prof. Hao-Li Zhang

      Article first published online: 27 FEB 2013 | DOI: 10.1002/asia.201201154

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      When shape matters: A facile phosphine-free method for synthesizing PbSe nanocrystals (NCs) with well-controlled size and morphology is reported. These high quality NCs were obtained by the reaction of elemental Se and PbCl2 using oleylamine as both the ligand and reaction medium. The as-produced PbSe NCs display strong optical limiting effects.

    2. Hydrogenation

      Selective Semihydrogenation of Alkynes on Shape-Controlled Palladium Nanocrystals (pages 919–925)

      Jooyoung Chung, Chanhoi Kim, Hansaem Jeong, Prof. Taekyung Yu, Do Huy Binh, Prof. Jyongsik Jang, Prof. Jaichan Lee, Prof.  B. Moon Kim and Prof. Byungkwon Lim

      Article first published online: 6 MAR 2013 | DOI: 10.1002/asia.201201166

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      Catalysis3: The semihydrogenation of various alkynes by Pd nanocubes was investigated. The nanocubes exhibited high alkene selectivity and complete cis-selectivity, thus surpassing the Lindlar catalyst. The shape control of Pd nanocrystals provides a simple and efficient way for generating highly selective catalysts for the semihydrogenation of alkynes.

    3. Self-Assembly

      Hydrogen-Bonding-Induced Polymorphous Phase Transitions in 2D Organic Nanostructures (pages 926–933)

      Li Xu, Dr. Xinrui Miao, Bao Zha and Prof. Dr. Wenli Deng

      Article first published online: 27 FEB 2013 | DOI: 10.1002/asia.201201229

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      Finger on the pulse: The 2D self-assembly of 2-hydroxy-7-alkoxy-9-fluorenones has been investigated by STM. The structural transition was driven by a voltage pulse applied to the STM tip, owing to the existence of different types of hydrogen bonds.

    4. Nanoparticles

      Surface-Passivated SBA-15-Supported Gold Nanoparticles: Highly Improved Catalytic Activity and Selectivity toward Hydrophobic Substrates (pages 934–938)

      Dr. Jinsuo Gao, Xueying Zhang, Yan Yang, Jun Ke, Prof. Xinyong Li, Prof. Yaobin Zhang, Prof. Feng Tan, Prof. Jingwen Chen and Prof. Xie Quan

      Article first published online: 12 MAR 2013 | DOI: 10.1002/asia.201300088

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      Passive aggressive: Surface-passivated SBA-15-supported gold nanoparticles that were almost superhydrophobic, with a contact angle of 144°, were prepared by surface passivation. The catalytic activity of this catalyst was more than 14-times that of non-passivated SBA-15 for the reduction of nitrobenzene. This method is a general method for the preparation of surface-passivated catalysts.

    5. Organic Sensitizers

      Novel Thiazolo[5,4-d]thiazole-Based Organic Dyes for Quasi-Solid-State Dye-Sensitized Solar Cells (pages 939–946)

      Weiyi Zhang, Quanyou Feng, Prof. Dr. Zhong-Sheng Wang and Prof. Dr. Gang Zhou

      Article first published online: 18 FEB 2013 | DOI: 10.1002/asia.201201202

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      Novel organic sensitizers containing the thiazolo[5,4-d]thiazole moiety have been designed and synthesized. A power conversion efficiency of 5.1 % was achieved for quasi-solid-state dye-sensitized solar cells based on (see figure).

    6. Amphiphiles

      Facile Synthesis and Photophysical Properties of Sphere–Square Shape Amphiphiles Based on Porphyrin–[60]Fullerene Conjugates (pages 947–955)

      Prof. Chien-Lung Wang, Wen-Bin Zhang, Xinfei Yu, Kan Yue, Hao-Jun Sun, Chih-Hao Hsu, Prof. Chain-Shu Hsu, Jojo Joseph, Prof. David A. Modarelli and Prof. Stephen Z. D. Cheng

      Article first published online: 20 FEB 2013 | DOI: 10.1002/asia.201201089

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      Square peg into a round hole: A facile route, based on Steglich esterification, was developed to efficiently synthesize a large variety of C60–porphyrin (Por)-based sphere–square shape amphiphiles (see picture). Photophysical studies suggest an edge-to-face alignment for the C60 and Por moieties.

    7. Porphyrins

      Zinc Porphyrins with a Pyridine-Ring-Anchoring Group for Dye-Sensitized Solar Cells (pages 956–962)

      Jianfeng Lu, Xiaobao Xu, Zhihong Li, Kun Cao, Jin Cui, Yibo Zhang, Prof. Yan Shen, Yi Li, Prof. Jun Zhu, Prof. Songyuan Dai, Prof. Wei Chen, Prof. Yibing Cheng and Prof. Mingkui Wang

      Article first published online: 19 FEB 2013 | DOI: 10.1002/asia.201201136

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      Anchorman: Porphyrin dyes that contained pyridine moieties as an anchoring group showed intense light adsorption and broadening of their absorption peak. These porphyrin complexes were successfully employed as sensitizers in dye-sensitized solar cells, which exhibited a power-conversion efficiency of 4 % under full-sunlight irradiation (AM 1.5G, 100 mW cm−2).

    8. Cluster Compounds

      Trigonal-Bipyramidal and Square-Pyramidal Chromium[BOND]Manganese Chalcogenide Clusters, [E2CrMn2(CO)n]2− (E=S, Se, Te; n=9, 10): Synthesis, Electrochemistry, UV/Vis Absorption, and Computational Studies (pages 963–973)

      Prof. Dr. Minghuey Shieh, Chun-Hsien Yu, Yen-Yi Chu, Yu-Wen Guo, Chung-Yi Huang, Kai-Jieah Hsing, Pei-Chi Chen and Chung-Feng Lee

      Article first published online: 18 FEB 2013 | DOI: 10.1002/asia.201201163

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      Show and tellurium: Cr[BOND]Mn trigonal-bipyramidal clusters, [E2CrMn2(CO)9]2− (E=S, Se, Te), their carbonylated square-pyramidal (SP) clusters, [E2CrMn2(CO)10]2− (E=Se, Te), and an arachno-cluster, [Te2CrMn2(CO)11]2−, are reported. The Te SP cluster was an electron-precise paramagnetic species, whilst the Se analogue diamagnetic. DFT calculations were performed to elucidate their formation, electrochemistry, and UV/Vis absorption.

    9. Nucleophilic Substitution

      The Efficiency of the Metal Catalysts in the Nucleophilic Substitution of Alcohols is Dependent on the Nucleophile and Not on the Electrophile (pages 974–981)

      Dr. Srijit Biswas and Dr. Joseph S. M. Samec

      Article first published online: 7 MAR 2013 | DOI: 10.1002/asia.201201178

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      Who's the boss? In a comprehensive study of catalytic SN1 type direct substitution of alcohols, the catalysts do not show any general variance in efficiency or selectivity with respect to the alcohols but are highly variable with respect to the nucleophiles. The reactivity of the alcohols is independent of the electrophilicity of the generated carbocations but highly dependent on the ease of formation of the cation.

    10. Metal–Organic Frameworks

      Mixed-Ligand Zn-MOFs for Highly Luminescent Sensing of Nitro Compounds (pages 982–989)

      Hao Wang, Dr. Weiting Yang and Prof. Zhong-Ming Sun

      Article first published online: 20 FEB 2013 | DOI: 10.1002/asia.201201184

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      Don't lose trace: Three ZnII metal–organic frameworks (Zn-MOFs) based on mixed ligands have been synthesized by a hydrothermal method. Compounds 1 and 2 are 3-dimensional frameworks, and 3 is a layered structure. Changes in the luminescence of the three Zn-MOFs dispersed in different solvents allow for the detection of trace amounts of nitro compounds through a fluorescence quenching mechanism.

    11. Self-Assembly

      Facile Fabrication of Nanorod-Assembled Fluorine-Substituted Hydroxyapatite (FHA) Microspheres (pages 990–996)

      Yueyue Wang, Prof. Dr. Chengtie Wu, Dr. Kaili Lin and Prof. Dr. Jiang Chang

      Article first published online: 12 FEB 2013 | DOI: 10.1002/asia.201201233

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      Hot rods: Nanorod-assembled FHA microspheres with controllable F contents were synthesized through a facile one-step method without using any template directing agent. The self-assembly process was elucidated according to the change of the morphology of the FHA crystals under different conditions. In addition, FHA showed higher chemical stability than HA under acidic conditions.

    12. Michael Addition

      Synthesis of Optically Enriched Spirocyclic Benzofuran-2-ones by Bifunctional Thiourea-Base Catalyzed Double-Michael Addition of Benzofuran-2-ones to Dienones (pages 997–1003)

      Prof. Xin Li, Chen Yang, Jia-Lu Jin, Xiao-Song Xue and Prof. Jin-Pei Cheng

      Article first published online: 19 FEB 2013 | DOI: 10.1002/asia.201201244

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      A double take: A highly enantioselective catalytic double-Michael addition reaction of substituted benzofuran-2-ones with divinyl ketones promoted by readily accessible tertiary amine–thiourea Cinchona alkaloids has been developed. A number of optically enriched spirocyclic benzofuran-2-ones were prepared in very good yields (up to 99 %), diastereoselectivities (up to 19:1 d.r.), and very good enantioselectivities (up to 92 % ee).

    13. Porphyrins

      Light Energy Collection in a Porphyrin–Imide–Corrole Ensemble (pages 1004–1014)

      Adina I. Ciuciu, Dr. Lucia Flamigni, Dr. Roman Voloshchuk and Prof. Dr. Daniel T. Gryko

      Article first published online: 26 FEB 2013 | DOI: 10.1002/asia.201300014

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      Let′s get (co)rolling: Light absorption in an assembly consisting of a free-base corrole and a Zn porphyrin connected by 1,8 naphthaleneimide results in a sequence of electronic energy transfer processes, ultimately concentrating the energy at the corrole extremity with a yield higher than 90 %.

    14. Porphyrinoids

      Synthesis and Photophysical Properties of Doubly β-to-β Bridged Cyclic ZnII Porphyrin Arrays (pages 1015–1022)

      Qingshan Hao, Dr. Yi Zeng, Dr. Tianjun Yu, Dr. Jinping Chen, Prof. Dr. Guoqiang Yang and Prof. Dr. Yi Li

      Article first published online: 27 FEB 2013 | DOI: 10.1002/asia.201300035

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      Do you cross the bridge or do you fade away: Doubly β-to-β bridged cyclic ZnII porphyrin arrays with carbazole, fluorene, and fluorenone as bridges were constructed. The incorporation of bridge units with different electronic effects results in different photophysical properties of the cyclic ZnII porphyrin arrays.

    15. Energetic Compounds

      Tetraanionic Nitrogen-Rich Tetrazole-Based Energetic Salts (pages 1023–1028)

      Dharavath Srinivas, Dr. Vikas D. Ghule, Dr. Krishnamurthi Muralidharan and Prof. H. Donald B. Jenkins

      Article first published online: 18 FEB 2013 | DOI: 10.1002/asia.201300033

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      Salty but sweet: 1,1,3,3-Tetra(1H-tetrazol-5-yl)propane-based energetic salts were synthesized in a simple and straightforward manner. These salts showed high positive enthalpies of formation, high nitrogen content, good thermal stabilities, and showed moderate detonation properties.

    16. Cross-Coupling Reactions

      Manganese-Catalyzed Cross-Coupling of Thiols with Aryl Iodides (pages 1029–1034)

      Tsung-Jui Liu, Chih-Lun Yi, Chien-Ching Chan and Prof. Dr. Chin-Fa Lee

      Article first published online: 6 MAR 2013 | DOI: 10.1002/asia.201300045

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      Coming up for ArI: A manganese-catalyzed cross-coupling reaction of thiols with aryl iodides that furnishes aryl thioethers in good to excellent yields has been reported. Functional groups such as unprotected alcohols and chloro substituents are tolerated under these reaction conditions. Moreover, this catalytic system enables the sterically demanding aryl iodides to couple with thiols (see scheme; R=aryl or alkyl).

    17. Quantum Dots

      Chemical Regulation of Carbon Quantum Dots from Synthesis to Photocatalytic Activity (pages 1035–1041)

      Dr. Shengliang Hu, Ruixue Tian, Lingling Wu, Qing Zhao, Prof. Jinlong Yang, Prof. Jun Liu and Shirui Cao

      Article first published online: 25 FEB 2013 | DOI: 10.1002/asia.201300076

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      Outer beauty: The sizes and surface states of carbon quantum dots (CQDs) were tuned by chemical methods. The photoluminescent behavior is related to both the sizes and surface states of the CQDs, but the photocatalytic activities are determined by the surface states alone. The separation and recombination of electron–hole pairs are determined by the degree of upward band bending induced by oxygen-containing groups on the surface of CQDs.

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