Dalton Transactions Blog

Gold nanoparticles (Au-NPs) are attractive for applications in important technological fields as components of biosensors, novel catalysts and new optical, magnetic or electrical devices. Traditional techniques for their preparation include thermal decomposition of organometallic precursors, chemical reduction of Au(I) ions, and electrochemical and photochemical processes. Methods based on reduction by sodium borohydride or citrate ions have been used successfully as the reducing agent acts also as a stabilizer and prevents further aggregation.

As an alternative, Heinrich Lang, from Chemnitz University of Technology, and coworkers have developed a family of gold(I) carboxylate complexes which can be used as precursors for the preparation of Au-NPs in a single step. The ligand works as the reducing and stabilizing part, simultaneously, in one molecule. After thermally induced decomposition of the complexes, Au-NPs are obtained with sizes in the range from 3.3 to 6.5 nm, and almost homogenous size distribution. The ethylene glycol-functionalized carboxylates were obtained from easy chemical reactions using available ethylene gycol or directly from commercial suppliers, and the complexes obtained by a two step procedure.  The authors report than larger chain lengths increased stability and slowed particle growth.

To find out more about it, read the full paper in Dalton Transactions.

Gold nanoparticles generated by thermolysis of “all-in-one” gold(I) carboxylate complexes
André Tuchscherer, Dieter Schaarshmidt, Steffen Schulze, Michael Hietschold, Heinrich Lang,
Dalton Transactions, 2012, Advance Article
DOI: 10.1039/c2dt11748g

To catch a bacterial infection after a visit to a hospital for a health checkup is not a funny way to become sick. Even worse is when the infection came from a device which was supposed to help you to get better, not sicker, such as a medical device. Intra-hospital infections are difficult to avoid as some viruses or bacterias deposit on any surface available, which may become in contact with a healthy person, with potential health consequences.  Numerous approaches have been looked at in order to create materials with anti-bacterial capabilities. In this direction, silver and copper nanoparticles (AgNP and CuNP) are attractive as they may be able to avoid propagation of several microorganisms, including E. coli and S. aureus. Several methods have been tried to successfully immobilize the nanoparticles to a surface.

Giacomo Dacarro and coworkers at the Università degli Studi di Pavia at Italy, have devised a new way to chemically modify Si-OH terminated surfaces (glass, quartz, SiO₂) by using a novel silane-derivatized polyethylenimine (PEI) and testing its ability to coordinate Ag⁺ and Cu²⁺ ions, and silver nanoparticles. The functionalized glasses are very effective in fighting against E. coli and S. aureus propagation, and may be an novel platform for use in designing smart, hybrid multifunctional materials.

Read more about his paper published in Dalton Transactions.

Monolayers of polyethilenimine on flat glass: a versatile platform for cations coordination and nanoparticles grafting in the preparation of antibacterial surfaces
Giacomo Dacarro, Lucia Cucca, Pietro Grisoli, Piersandro Pallavicini, Maddalena Patrini and Angelo Taglietti
Dalton Trans., Advance Article, 2012.
DOI: 10.1039/c1dt11373a 

Noble metals are highly regarded as unique catalysts for use in several reactions, many of them of interest for the pharmaceutical industry. However, their cost may be a reason why not to be considered in several applications.  When used in the form of nanoparticles, an increase of their activity is expected as a result of their large specific surface area, even when small amounts are used, which can save money and time. In the search for more efficient ways to form C-N bonds, a variety of homogenous catalysts such as Cu, Pd and Rh have been investigated in order to tune them and improve their ability to promote cross-coupling reactions among aryl halides and amines. Specifically, copper mediated Ullmann condensation is attractive as it is cheaper than Pd or Rh.

Zhenhui Kang and his group at the Institute of Functional Nano and Soft Materials and the Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices at Soochow University have developed a new catalyst based on copper nanoparticles inmovilized on silicon nanowires (CuNPs@SiNWs). This catalyst is able to enhance the coupling reaction at 110 °C among benzene halides and aniline in good yields, without the use of any ligand or additive. Even deactivated aryl bromides and inert chlorobenzene were reactive under the action of this novel catalysts. The authors suggest that the use of SiNWs as an alternative substrate support may be of interest of other researchers in the quest of superior heterogeneous catalysts.  

For further information, read the work by Zhenhui Kang and coworkers published in Dalton Transactions.

Copper nanoparticles modified silicon nanowires with enhanced cross-coupling catalytic ability
Keming Pan, Hai Ming, Hang Yu, Hui Huang, Yang Liu, Zhenhui Kang
Dalton Trans., Advance Article, 2012.
DOI: 10.1039/c2dt12182d

The Dalton Transactions team wishes you every success in the Year of the Dragon, and we hope that you enjoy your New Year holiday.

In celebration we have made these recently promoted Dalton Transactions Hot articles free to access for the whole of February:

Ba2AgInS4 and Ba4MGa5Se12 (M = Ag, Li): syntheses, structures, and optical properties
Wenlong Yin, Kai Feng, Dajiang Mei, Jiyong Yao, Peizhen Fu and Yicheng Wu
DOI: 10.1039/C2DT11895E

Synthesis and properties of a dendritic FRET donor–acceptor system with cationic iridium(III) complex core and carbazolyl periphery
Yanfang Li, Yang Liu and Ming Zhou
DOI: 10.1039/C1DT11716E

Three novel Bi(III) complexes with in situ generated anilate ligands: unusual oxidation of cyclohexanedione to dihydroxy benzoquinone
Hui Gao and Xian-Ming Zhang
DOI: 10.1039/C1DT11258A

(Zn, Mg)2GeO4:Mn2+ submicrorods as promising green phosphors for field emission displays: hydrothermal synthesis and luminescence properties
Mengmeng Shang, Guogang Li, Dongmei Yang, Xiaojiao Kang, Chong Peng, Ziyong Cheng and Jun Lin
DOI: 10.1039/C1DT10673B

Dalton Transactions supports an online virtual web community for inorganic chemists, providing links to international research groups, conferences and events, and highlighting the latest research in the field. Be a part of this by accessing the Dalton Transactions blog, following us on twitter or signing up to our e-alert service.

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This month sees the following articles in Dalton Transactions that are in the top ten most accessed:-

Water oxidation catalysed by manganese compounds: from complexes to ‘biomimetic rocks’ 
Mathias Wiechen, Hans-Martin Berends and Philipp Kurz 
Dalton Trans., 2012, 41, 21-31 DOI:10.1039/c1dt11537e 

Self-assembly in inorganic chemistry 
Paul E. Kruger and Thorfinnur Gunnlaugsson 
Dalton Trans., 2011, 40, 12003-12004 DOI:10.1039/c1dt90162a 

Paramagnetic metal complexes of diamido donor ligands 
Cassandra E. Hayes and Daniel B. Leznoff 
Dalton Trans., 2012, Advance Article DOI:10.1039/c1dt11559f 

A series of pillar-layer metal?organic frameworks based on 5-aminoisophthalic acid and 4,4′-bipyridine 
Hai-Ning Wang, Xing Meng, Chao Qin, Xin-Long Wang, Guang-Sheng Yang and Zhong-Min Su 
Dalton Trans., 2012, 41, 1047-1053 DOI:10.1039/c1dt11304f 

The future of metal-organic frameworks 
Neil R. Champness 
Dalton Trans., 2011, 40, 10311-10315 DOI:10.1039/c1dt11184a 

A cationic iridium(iii) complex showing aggregation-induced phosphorescent emission (AIPE) in the solid state: synthesis, characterization and properties 
Guo-Gang Shan, Ling-Yu Zhang, Hai-Bin Li, Shuang Wang, Dong-Xia Zhu, Peng Li, Chun-Gang Wang, Zhong-Min Su and Yi Liao 
Dalton Trans., 2012, 523-530 DOI:10.1039/c1dt11215e 

The structure and reactivity of iron nitride complexes 
Jeremy M. Smith and Deepak Subedi 
Dalton Trans., 2012, Advance Article DOI:10.1039/c1dt11674f 

A novel Zn4O-based triazolyl benzoate MOF: synthesis, crystal structure, adsorption properties and solid state 13C NMR investigations 
Jörg Lincke, Daniel Lässig, Karolin Stein, Jens Moellmer, Anusree Viswanath Kuttatheyil, Christian Reichenbach, Andreas Moeller, Reiner Staudt, Grit Kalies, Marko Bertmer and Harald Krautscheid 
Dalton Trans., 2012, 817-824 DOI:10.1039/c1dt11431j 

Stepwise synthesis of a hydrido, N-heterocyclic dicarbene iridium(iii) pincer complex featuring mixed NHC/abnormal NHC ligands 
Weiwei Zuo and Pierre Braunstein 
Dalton Trans., 2012, 41, 636-643 DOI:10.1039/c1dt11511a 

Luminescent Ir(iii) complexes containing benzothiazole-based tridentate ligands: synthesis, characterization, and application to organic light-emitting diodes 
Junpei Kuwabara, Tomomi Namekawa, Masa-aki Haga and Takaki Kanbara 
Dalton Trans., 2012, 41, 44-46 DOI:10.1039/c1dt11560j 

Why not take a look at the articles today and blog your thoughts and comments below.

Fancy submitting an article to Dalton Transactions? Then why not submit to us today or alternatively email us  your suggestions.

Discover the beautiful outside cover of Dalton Transactions issue 47.  The  authors would like to gratefully acknowledge Mrs. Kshitija Kolvankar for the design of the cover page highlighting the work of Serrano and co-workers  in developing a simple and novel synthetic route towards solvate analogous of classical solvate precursors.  It involves stirring Pd₃(AcO)₆ in the solvent of choice, in the stoichiometric presence of protic ligands. The examples presented with imidate ligands allowed the preparation of acetonitrile, dimethylsulfoxide and dimetylsulfide bis-imidate complexes.  The possibility of extending the route presented to other combinations of solvents/protic electrophiles makes it a potentially useful synthetic tool, and also promising applications in catalysis could be expected for the new precursor and its derivatives.

Read more at:

Bis(imidate)palladium(II) complexes with labile ligands. Mimics of classical precursors?
Gregorio Sánchez, Joaquín García, Marina Martínez, Anant R. Kapdi, José Pérez, Luis García and J. Luis Serrano
Dalton Trans., 2011, 40, 12676-12689
DOI: 10.1039/C1DT10426H

The inside front cover highlights research from Huang et al.

Read more at:

A new photocatalyst: Bi2TiO4F2 nanoflakes synthesized by a hydrothermal method
Shaoying Wang, Baibiao Huang, Zeyan Wang, Yuanyuan Liu, Wei Wei, Xiaoyan Qin, Xiaoyang Zhang and Ying Dai
Dalton Trans., 2011, 40, 12670-12675
DOI: 10.1039/C1DT10889A