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You searched for: Journal name Chemical communications Remove constraint Journal name: Chemical communications Publication year rev 7986-2014 Remove constraint Publication year rev: 7986-2014 Subject term catalysts Remove constraint Subject term: catalysts
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1. A 3-D diamondoid MOF catalyst based on in situ generated [Cu(L)₂] N-heterocyclic carbene (NHC) linkers: hydroboration of CO₂

Author:
Alexandre Burgun; Rachel S. Crees; Marcus L. Cole; Christian J. Doonan; Christopher J. Sumby
Source:
Chemical communications 2014 v.50 no.79 pp. 11760-11763
ISSN:
1364-548X
Subject:
carbenes; carbon dioxide; catalysts; chemical reactions; copper; heterocyclic nitrogen compounds; moieties
Abstract:
... A new MOF, [Zn₄O{Cu(L)₂}₂] (1), with a 4-fold interpenetrated 3D diamondoid structure was synthesised from in situ generated [Cu(L)₂] NHC linkers. MOF 1 possesses tetrahedral Zn₄O nodes, which are unusually coordinated by four pairs of carboxylates from four [Cu(L)₂] linkers, and 14 Å 1-D pore channels lined with [Cu(L)₂] moieties that catalyse the hydroboration of CO₂. ...
DOI:
10.1039/c4cc04761c

2. A Lewis acid activated reaction of Zn with EtI to promote highly enantioselective alkyne additions to aldehydes

Author:
Shan-yong Chen; Winnie Liu; Xuedan Wu; Jun Ying; Xiaoqi Yu; Lin Pu
Source:
Chemical communications 2014 v.51 no.2 pp. 358-361
ISSN:
1364-548X
Subject:
Lewis acids; alcohols; aldehydes; alkynes; ambient temperature; catalysts; chemical reactions; enantioselectivity; zinc
Abstract:
... An easily available BINOL–Ti(OⁱPr)₄ catalyst system is found to activate the reaction of Zn powder with EtI for the asymmetric alkyne addition to aldehydes at room temperature. It allows the synthesis of a number of synthetically useful chiral propargylic alcohols with both high yields and high enantioselectivity (up to >96% ee). ...
DOI:
10.1039/c4cc08031a

3. A Ni(ii)-MOF: reversible guest adsorption and heterogeneous catalytic properties for silylcyanation of aromatic aldehydes

Author:
Xiao-Meng Zhang; Chao-Wei Zhao; Jian-Ping Ma; Yang Yu; Qi-Kui Liu; Yu-Bin Dong
Source:
Chemical communications 2014 v.51 no.5 pp. 839-842
ISSN:
1364-548X
Subject:
adsorption; aldehydes; aromatic compounds; catalysts; catalytic activity; chemical reactions; iodine; ligands; nickel; solvents
Abstract:
... A porous Ni(ii)-MOF, which was constructed from a new bent fluorene-bridged ligand and NiCl₂ under solvothermal conditions, can reversibly uptake organic solvent molecules and iodine species in a single-crystal-to-single-crystal (SC–SC) fashion. Furthermore, the obtained I₂⊂Ni(ii)-MOF can be a highly active heterogeneous catalyst to promote solvent-free silylcyanation of aromatic aldehydes under m ...
DOI:
10.1039/c4cc08003c

4. A chameleon catalyst for nonheme iron-promoted olefin oxidation

Author:
Shyam R. Iyer; Maedeh Moshref Javadi; Yan Feng; Min Young Hyun; Williamson N. Oloo; Cheal Kim; Lawrence Que
Source:
Chemical communications 2014 v.50 no.89 pp. 13777-13780
ISSN:
1364-548X
Subject:
Lewis acids; Lewis bases; acetic acid; catalysts; epoxidation reactions; hydrogen peroxide; iron; olefin; oxidants; oxidation
Abstract:
... We report the chameleonic reactivity of two nonheme iron catalysts for olefin oxidation with H₂O₂ that switch from nearly exclusive cis-dihydroxylation of electron-poor olefins to the exclusive epoxidation of electron-rich olefins upon addition of acetic acid. This switching suggests a common precursor to the nucleophilic oxidant proposed to Feᴵᴵᴵ-η²-OOH and electrophilic oxidant proposed to Feⱽ(O ...
DOI:
10.1039/c4cc06164k

5. A cobalt–NHC complex as an improved catalyst for photochemical hydrogen evolution from water

Author:
Ken Kawano; Kosei Yamauchi; Ken Sakai
Source:
Chemical communications 2014 v.50 no.69 pp. 9872-9875
ISSN:
1364-548X
Subject:
carbenes; catalysts; cobalt; heterocyclic nitrogen compounds; hydrogen; hydrogen production; pH; photochemistry; ruthenium
Abstract:
... A macrocyclic N-heterocyclic carbene (NHC)–cobalt complex was found to act as an improved H₂-evolving catalyst in a [Ru(bpy)₃]²⁺-sensitized photosystem using methylviologen as a redox acceptor (MV²⁺ + e⁻ → MV⁺˙, MV²⁺ = N,N′-dimethyl-4,4′-bipyridinium), which provides a driving force of only 150 meV for H₂ evolution at pH 5.0. ...
DOI:
10.1039/c4cc03493g

6. A cooperative Pd–Cu system for direct C–H bond arylation

Author:
Mathieu Lesieur; Faïma Lazreg; Catherine S. J. Cazin
Source:
Chemical communications 2014 v.50 no.64 pp. 8927-8929
ISSN:
1364-548X
Subject:
aromatic hydrocarbons; arylation; carbon-hydrogen bond activation; catalysts; chemical bonding; chlorides; copper; organobromine compounds
Abstract:
... A novel and efficient method for C–H arylation using well-defined Pd– and Cu–NHC systems has been developed. This process promotes the challenging construction of C–C bonds from arenes or heteroarenes using aryl bromides and chlorides. Mechanistic studies show that [Cu(OH)(NHC)] plays a key role in the C–H activation and is involved in the transmetallation with the Pd–NHC co-catalyst. ...
DOI:
10.1039/c4cc03201b

7. A copper(i)/copper(ii)–salen coordination polymer as a bimetallic catalyst for three-component Strecker reactions and degradation of organic dyes

Author:
Yun-Long Hou; Raymond Wai-Yin Sun; Xiao-Ping Zhou; Jun-Hao Wang; Dan Li
Source:
Chemical communications 2014 v.50 no.18 pp. 2295-2297
ISSN:
1364-548X
Subject:
catalysts; catalytic activity; coordination polymers; copper; dyes; light; lighting; photolysis
Abstract:
... A copper(i)/copper(ii)–salen coordination polymer prepared by solvothermal reactions shows prominent bimetallic catalytic activities towards three-component Strecker reactions and photodegradation of organic dyes under visible-light illumination. ...
DOI:
10.1039/c3cc47996j

8. A dual site catalyst for mild, selective nitrile reduction

Author:
Zhiyao Lu; Travis J. Williams
Source:
Chemical communications 2014 v.50 no.40 pp. 5391-5393
ISSN:
1364-548X
Subject:
borates; boron; catalysts; chemical reactions; ruthenium
Abstract:
... We report a novel ruthenium bis(pyrazolyl)borate scaffold that enables cooperative reduction reactivity in which boron and ruthenium centers work in concert to effect selective nitrile reduction. The pre-catalyst compound [κ³-(1-pz)₂HB(N = CHCH₃)]Ru(cymene)⁺ TfO⁻ (pz = pyrazolyl) was synthesized using readily-available materials through a straightforward route, thus making it an appealing catalyst ...
DOI:
10.1039/c3cc47384h
PubMed:
24409456
PubMed Central:
PMC3999263

9. A dye-sensitized Pt@UiO-66(Zr) metal–organic framework for visible-light photocatalytic hydrogen production

Author:
Jiao He; Jiaqiang Wang; Yongjuan Chen; Jinping Zhang; Deliang Duan; Yao Wang; Zhiying Yan
Source:
Chemical communications 2014 v.50 no.53 pp. 7063-7066
ISSN:
1364-548X
Subject:
catalysts; coordination polymers; dyes; hydrogen production; light; lighting; photocatalysis; rhodamines; zirconium
Abstract:
... A stable photoactive metal–organic framework UiO-66(Zr) sensitized by adsorbed or directly added rhodamine B dye exhibited photocatalytic activity for hydrogen evolution under visible-light illumination (λ ≥ 420 nm). Using Pt as a co-catalyst, the adsorbed and directly added dye extremely enhanced the photocatalytic activity to 30 and 26 times the value afforded by bare Pt@UiO-66(Zr), respectively ...
DOI:
10.1039/c4cc01086h

10. A facile approach for the preparation of tunable acid nano-catalysts with a hierarchically mesoporous structure

Author:
Youngbo Choi; Yang Sik Yun; Hongseok Park; Dae Sung Park; Danim Yun; Jongheop Yi
Source:
Chemical communications 2014 v.50 no.57 pp. 7652-7655
ISSN:
1364-548X
Subject:
catalysts; catalytic activity; catalytic cracking; chemical compounds; hydrolysis; nanospheres; porous media; sucrose
Abstract:
... A facile and efficient approach to prepare hierarchically and radially mesoporous nano-catalysts with tunable acidic properties has been successfully developed. The nanospheres show excellent catalytic performance for the acid catalysed reactions, i.e. cracking of 1,3,5-triisopropylbenzene and hydrolysis of sucrose. ...
DOI:
10.1039/c4cc01881h

11. A high efficiency CoCr₂O₄/carbon nanotubes nanocomposite electrocatalyst for dye-sensitised solar cells

Author:
Mingxing Guo; Beibei Tang; Haimin Zhang; Shuhui Yin; Wei Jiang; Yiming Zhang; Mengying Li; Hui Wang; Liqi Jiao
Source:
Chemical communications 2014 v.50 no.55 pp. 7356-7358
ISSN:
1364-548X
Subject:
carbon nanotubes; catalysts; catalytic activity; chemical compounds; chemical reactions; electrochemistry; nanocomposites; solar cells; solar energy
Abstract:
... A CoCr₂O₄/carbon nanotubes (CoCr₂O₄/CNTs) nanocomposite was successfully synthesised by a facile solution route, and used as an electrocatalyst for dye-sensitised solar cells (DSSCs) for the first time, exhibiting a comparable power conversion efficiency of 8.40% to Pt-based DSSCs (η = 8.68%) owing to the superior electrocatalytic activity of the nanocomposite. ...
DOI:
10.1039/c4cc03221g

12. A high-performance electrocatalyst for oxygen evolution reactions based on electrochemical post-treatment of ultrathin carbon layer coated cobalt nanoparticles

Author:
Qingqing Xiao; Yuxia Zhang; Xin Guo; Lin Jing; Zhiyu Yang; Yifei Xue; Yi-Ming Yan; Kening Sun
Source:
Chemical communications 2014 v.50 no.86 pp. 13019-13022
ISSN:
1364-548X
Subject:
carbon; catalysts; chemical reactions; cobalt; electrochemistry; nanoparticles; oxygen production
Abstract:
... Electrochemical post-treatment of ultrathin carbon layer coated cobalt nanoparticles generates a novel electrocatalyst, affording a small overpotential of 333 mV at a current density of 10 mA cm⁻² and a small Tafel slope of ∼58 mV per decade. ...
DOI:
10.1039/c4cc05953k

13. A highly Lewis-acidic Pd(iv) surface on Pd@SiO₂ nanocatalysts for hydroalkoxylation reactions

Author:
Mijong Kim; Suyeon Lee; Kiseong Kim; Dongwoo Shin; Hyunwoo Kim; Hyunjoon Song
Source:
Chemical communications 2014 v.50 no.95 pp. 14938-14941
ISSN:
1364-548X
Subject:
catalysts; catalytic activity; iodobenzenes; nanomaterials; oxidation; palladium; silica
Abstract:
... The Pd(iv) species, known to be critical intermediates in homogeneous catalysis, were successfully generated on the surface of Pd nanocatalysts via oxidation with iodobenzene dichloride (PhICl₂) or N-chlorosuccinimide (NCS). In particular, the Pd@SiO₂ yolk–shell nanocatalyst activated by PhICl₂ showed high reactivity and superior stability to the other Pd-based catalysts for hydroalkoxylation reac ...
DOI:
10.1039/c4cc05112b

14. A highly active PtCu₃ intermetallic core–shell, multilayered Pt-skin, carbon embedded electrocatalyst produced by a scale-up sol–gel synthesis

Author:
M. Bele; P. Jovanovič; A. Pavlišič; B. Jozinović; M. Zorko; A. Rečnik; E. Chernyshova; S. Hočevar; N. Hodnik; M. Gaberšček
Source:
Chemical communications 2014 v.50 no.86 pp. 13124-13126
ISSN:
1364-548X
Subject:
carbon; catalysts; cathodes; chemical reactions; electrochemistry; fuel cells; nanoparticles; platinum; temperature
Abstract:
... We present a novel, scaled-up sol–gel synthesis which enables one to produce 20 g batches of highly active and stable carbon supported PtCu₃ nanoparticles as cathode materials for low temperature fuel cell application. We confirm the presence of an ordered intermetallic phase underneath a multilayered Pt-skin together with firm embedment of nanoparticles in the carbon matrix. ...
DOI:
10.1039/c4cc05637j

15. A hybrid polyoxometalate–organic molecular catalyst for visible light driven water oxidation

Author:
C. Zhang; X. Lin; Z. Zhang; L.-S. Long; C. Wang; W. Lin
Source:
Chemical communications 2014 v.50 no.78 pp. 11591-11594
ISSN:
1364-548X
Subject:
catalysts; light; oxidation; pyridines
Abstract:
... A novel organic–inorganic hybrid monocapped/bicapped Keggin structure [Coᴵᴵ(bpy)₃]₆(H₂bpy)[(Coᴵᴵbpy)₂(PMo₈ⱽᴵMo₄ⱽO₄₀)]₃ [(Coᴵᴵbpy)(PMo₈ⱽᴵMo₄ⱽO₄₀)]·16H₂O (bpy = 2,2′-bipyridine) was synthesized and shown to be an efficient visible light-driven catalyst for water oxidation. ...
DOI:
10.1039/c4cc03487b

16. A local proton source in a [Mn(bpy-R)(CO)₃Br]-type redox catalyst enables CO₂ reduction even in the absence of Brønsted acids

Author:
Federico Franco; Claudio Cometto; Federico Ferrero Vallana; Fabrizio Sordello; Emanuele Priola; Claudio Minero; Carlo Nervi; Roberto Gobetto
Source:
Chemical communications 2014 v.50 no.93 pp. 14670-14673
ISSN:
1364-548X
Subject:
Bronsted acids; carbon dioxide; catalysts; catalytic activity; chemical reduction; electrochemistry; manganese
Abstract:
... The effect of a local proton source on the activity of a bromotricarbonyl Mn redox catalyst for CO₂ reduction has been investigated. The electrochemical behaviour of the novel complex [fac-Mn(dhbpy)(CO)₃Br] (dhbpy = 4-phenyl-6-(1,3-dihydroxybenzen-2-yl) 2,2′-bipyridine), containing two acidic OH groups in the proximity of the metal centre, under a CO₂ atmosphere showed a sustained catalysis in hom ...
DOI:
10.1039/c4cc05563b

17. A masked diboron in Cu-catalysed borylation reaction: highly regioselective formal hydroboration of alkynes for synthesis of branched alkenylborons

Author:
Hiroto Yoshida; Yuki Takemoto; Ken Takaki
Source:
Chemical communications 2014 v.50 no.61 pp. 8299-8302
ISSN:
1364-548X
Subject:
alkynes; aromatic compounds; boron; boron compounds; carbenes; catalysts; catalytic activity; chemical reactions; regioselectivity
Abstract:
... The use of a masked diboron as a boron source in the presence of a Cu–N-heterocyclic carbene (NHC) catalyst enables alkyl-, aryl-, heteroatom- and silyl-substituted terminal alkynes to undergo α-selective formal hydroboration to give diverse branched alkenylboron compounds exclusively. Synthetic potential of this α-selective hydroboration has been demonstrated by total synthesis of pharmaceuticall ...
DOI:
10.1039/c4cc01757a

18. A metal free domino synthesis of 3-aroylindoles via two sp³ C–H activation

Author:
Anupal Gogoi; Anju Modi; Srimanta Guin; Saroj Kumar Rout; Debapratim Das; Bhisma K. Patel
Source:
Chemical communications 2014 v.50 no.72 pp. 10445-10447
ISSN:
1364-548X
Subject:
amines; carbon-hydrogen bond activation; catalysts; chemical reactions; oxidants
Abstract:
... A metal free synthesis of 3-aroylindole involving two sp³ C–H activation has been achieved starting from o-alkynyl-N,N-dialkylamines using catalyst TBAI and oxidant TBHP. ...
DOI:
10.1039/c4cc04407j

19. A modular tyrosine kinase deoxyribozyme with discrete aptamer and catalyst domains

Author:
Victor Dokukin; Scott K. Silverman
Source:
Chemical communications 2014 v.50 no.66 pp. 9317-9320
ISSN:
1364-548X
Subject:
DNA; adenosine triphosphate; catalysts; catalytic activity; chemical compounds; enzymes; oligonucleotides; phosphorylation; tyrosine
Abstract:
... We assess the utility of integrating a predetermined aptamer DNA module adjacent to a random catalytic DNA region for identifying new deoxyribozymes by in vitro selection. By placing a known ATP aptamer next to an N₄₀ random region, an explicitly modular DNA catalyst for tyrosine side chain phosphorylation is identified. The results have implications for broader identification of deoxyribozymes th ...
DOI:
10.1039/c4cc04253k
PubMed:
25000337
PubMed Central:
PMC4126072

20. A molecular structural analog of proposed dinuclear active sites in cobalt-based water oxidation catalysts

Author:
Timothy C. Davenport; Hyun S. Ahn; Micah S. Ziegler; T. Don Tilley
Source:
Chemical communications 2014 v.50 no.48 pp. 6326-6329
ISSN:
1364-548X
Subject:
active sites; carbon dioxide; catalysts; catalytic activity; cobalt; electrochemistry; nitrates; oxidation; oxygen; phosphates
Abstract:
... The compound [Co₂(μ-OH)₂(OH₂)₂(DPFN)][NO₃]₄ is a molecular structural analog of proposed active sites of cobalt phosphate water oxidation catalysts. Computational studies on this system indicate feasible catalytic pathways to oxygen formation, despite the low electrocatalytic activity observed for [Co₂(μ-OH)₂(OH₂)₂(DPFN)][NO₃]₄. Electrochemical and reactivity studies implicate the binding of phosp ...
DOI:
10.1039/c3cc46865h

21. A mononuclear cobalt complex with an organic ligand acting as a precatalyst for efficient visible light-driven water oxidation

Author:
Shao Fu; Yongdong Liu; Yong Ding; Xiaoqiang Du; Fangyuan Song; Rui Xiang; Baochun Ma
Source:
Chemical communications 2014 v.50 no.17 pp. 2167-2169
ISSN:
1364-548X
Subject:
catalysts; cobalt; ligands; oxidation; pH; perchlorates; photosensitizing agents
Abstract:
... N,N′-Bis(salicylidene)ethylenediaminecobalt(ii) (1) has been investigated as a highly efficient water oxidation precatalyst with a TON of 854 at pH = 9.0, using [Ru(bpy)₃](ClO₄)₂ as a photosensitizer and Na₂S₂O₈ as a sacrificial electron acceptor. ...
DOI:
10.1039/c3cc48059c

22. A nanodiamond/CNT–SiC monolith as a novel metal free catalyst for ethylbenzene direct dehydrogenation to styrene

Author:
Hongyang Liu; Jiangyong Diao; Qi Wang; Songyuan Gu; Tong Chen; Changxi Miao; Weimin Yang; Dangsheng Su
Source:
Chemical communications 2014 v.50 no.58 pp. 7810-7812
ISSN:
1364-548X
Subject:
catalysts; catalytic activity; dehydrogenation; ethylbenzene; nanodiamonds; styrene
Abstract:
... A novel nanodiamond/CNT–SiC monolith catalyst has been prepared by a facile two-step approach. The as-synthesized monolith afforded high activity and stability for ethylbenzene direct dehydrogenation to styrene, showing its potential application as a metal free catalyst in gaseous catalytic reactions. ...
DOI:
10.1039/c4cc01693a

23. A new class of electrocatalysts of supporting Pt on an Engel–Brewer alloy substrate: a demonstration for oxidation of ethylene glycol

Author:
X. F. Yang; W. Xu; M. Li; B. E. Koel; J. G. Chen
Source:
Chemical communications 2014 v.50 no.85 pp. 12981-12984
ISSN:
1364-548X
Subject:
alloys; carbon dioxide; catalysts; catalytic activity; electrochemistry; ethylene glycol; iridium; oxidation; platinum
Abstract:
... A novel electrocatalytic surface consisting of a Pt monolayer (ML) on an Hf–Ir alloy substrate demonstrated significantly higher activity (six times) and higher selectivity to CO₂ formation than bulk Pt in oxidizing ethylene glycol. This enhanced performance could be associated with the high reducibility of Hf oxide and altered electronic property of the Pt ML. ...
DOI:
10.1039/c4cc04006f

24. A new mild synthetic route to N-arylated pyridazinones from aryldiazonium salts

Author:
Ouissam El Bakouri; Daniel Cassú; Miquel Solà; Teodor Parella; Anna Pla-Quintana; Anna Roglans
Source:
Chemical communications 2014 v.50 no.59 pp. 8073-8076
ISSN:
1364-548X
Subject:
catalysts; chemical reactions; organic compounds; potassium; salts
Abstract:
... An efficient method for the synthesis of N-arylated pyridazinones from potassium 2-furantrifluoroborate and aryldiazonium salts is described. The reaction was run in water at 0–5 °C in short reaction times and without any catalyst or additive. A mechanistic proposal is made based on the experimental data and DFT calculations. ...
DOI:
10.1039/c4cc03190c

25. A novel high efficiency composite catalyst: single crystal triangular Au nanoplates supported by functional reduced graphene oxide

Author:
Weina Wang; Jiangjiang Gu; Wenwen Hua; Xudong Jia; Kai Xi
Source:
Chemical communications 2014 v.50 no.64 pp. 8889-8891
ISSN:
1364-548X
Subject:
catalysts; catalytic activity; chemical reactions; gold; graphene oxide; nanogold; p-nitrophenol
Abstract:
... To improve the utilization efficiency of Au catalyst, triangular Au nanoplates on functional reduced graphene oxide were prepared by a facile method. The products with ultra-low trace amounts of Au afforded high catalytic efficiency for the reduction of 4-nitro phenol. The morphology of the products was controlled by tuning the addition of HAuCl₄. ...
DOI:
10.1039/c4cc03306j

26. A novel iron complex for highly efficient catalytic hydrogen generation from the hydrolysis of organosilanes

Author:
Alan Kay Liang Teo; Wai Yip Fan
Source:
Chemical communications 2014 v.50 no.54 pp. 7191-7194
ISSN:
1364-548X
Subject:
catalysts; catalytic activity; hydrogen; hydrogen production; hydrolysis; iron; oxidation
Abstract:
... Hydrolytic oxidation of organosilanes based on an iron catalyst is described for the first time. The novel iron complex, [Fe(C₆H₅N₂O)(CO)(MeCN)₃][PF₆], exhibits excellent mediating power in the catalytic hydrolysis of organosilanes to produce dihydrogen and organosilanols with turnover numbers approaching 10⁴ and turnover frequencies in excess of 10² min⁻¹ under ambient conditions. ...
DOI:
10.1039/c4cc02852j

27. A novel mechanism for poisoning of metal oxide SCR catalysts: base–acid explanation correlated with redox properties

Author:
Huazhen Chang; Junhua Li; Wenkang Su; Yuankai Shao; Jiming Hao
Source:
Chemical communications 2014 v.50 no.70 pp. 10031-10034
ISSN:
1364-548X
Subject:
catalysts; chemical reactions; gases; hydrochloric acid; nitrous oxide; sulfur dioxide; temperature
Abstract:
... A novel mechanism is proposed for the poisoning effect of acid gases and N₂O formation on SCR catalysts involving base–acid properties correlated with redox ability of M–O or M–OH (M = Ce or V) of metal oxides and the strength of their basicity responsible for resistance to HCl and SO₂ at medium and low temperatures. ...
DOI:
10.1039/c4cc02991g

28. A novel oxidative procedure for the synthesis of benzamides from styrenes and amines under metal-free conditions

Author:
Muhammad Sharif; Jin-Long Gong; Peter Langer; Matthias Beller; Xiao-Feng Wu
Source:
Chemical communications 2014 v.50 no.36 pp. 4747-4750
ISSN:
1364-548X
Subject:
amines; benzamides; catalysts; chemical reactions
Abstract:
... An interesting procedure for the oxidative synthesis of amides from styrenes and amines has been developed. Various primary amides were formed in moderate yields (25–81%). Secondary amides can be produced in moderate yields as well (41–68%). Notably, no transition metal catalyst was needed for this transformation. This is the first example of oxidative transformation of styrenes to benzamides. ...
DOI:
10.1039/c4cc01054j

29. A one-pot, three-component reaction for the synthesis of novel 7-arylbenzo[c]acridine-5,6-diones

Author:
Shivani Mahajan; Sadhika Khullar; Sanjay K. Mandal; Inder Pal Singh
Source:
Chemical communications 2014 v.50 no.70 pp. 10078-10081
ISSN:
1364-548X
Subject:
aldehydes; aromatic amines; catalysts; chemical reactions; p-toluenesulfonic acid; reaction mechanisms; solvents
Abstract:
... A one pot domino protocol for an efficient synthesis of 7-arylbenzo[c]acridine-5,6-diones, with a novel nucleus, has been developed by reacting 2-hydroxynaphthalene-1,4-dione, aromatic aldehydes and aromatic amines using environmentally benevolent p-toluene sulphonic acid as a catalyst. An exciting feature of this communication is the reaction mechanism that depends on the reaction solvent. ...
DOI:
10.1039/c4cc03079f

30. A phthalimidation protocol that follows protein defined parameters

Author:
Rohith Singudas; Srinivasa Rao Adusumalli; Pralhad Namdev Joshi; Vishal Rai
Source:
Chemical communications 2014 v.51 no.3 pp. 473-476
ISSN:
1364-548X
Subject:
ambient temperature; amines; catalysts; chemical reactions; chemoselectivity; pH; proteins
Abstract:
... This work outlines the first phthalimidation protocol suitable for protein labeling and performed in aqueous media at room temperature and neutral pH with no catalyst or co-reagent required. The methodology is suitable for a range of amines and its efficiency was determined with chemoselective and site-selective protein labeling. ...
DOI:
10.1039/c4cc08503e

31. A porous metal–metalloporphyrin framework featuring high-density active sites for chemical fixation of CO₂ under ambient conditions

Author:
Wen-Yang Gao; Lukasz Wojtas; Shengqian Ma
Source:
Chemical communications 2014 v.50 no.40 pp. 5316-5318
ISSN:
1364-548X
Subject:
Lewis acids; active sites; ambient temperature; carbon dioxide; carbonates; catalysts; chemical reactions; copper; ligands; moieties; porphyrins
Abstract:
... Self-assembly of the custom-designed octatopic porphyrin ligand of tetrakis(3,5-dicarboxybiphenyl)porphine with the in situ generated Cu₂(CO₂)₄ paddlewheel moieties afforded a porous metal–metalloporphyrin framework, MMPF-9, which features a high density of Cu(ii) sites confined within nanoscopic channels and demonstrates excellent performances as a heterogeneous Lewis-acid catalyst for chemical f ...
DOI:
10.1039/c3cc47542e

32. A significant enhancement of catalytic activities in oxidation with H₂O₂ over the TS-1 zeolite by adjusting the catalyst wettability

Author:
Liang Wang; Jing Sun; Xiangju Meng; Weiping Zhang; Jian Zhang; Shuxiang Pan; Zhe Shen; Feng-Shou Xiao
Source:
Chemical communications 2014 v.50 no.16 pp. 2012-2014
ISSN:
1364-548X
Subject:
catalysts; catalytic activity; chemical communication; hydrogen peroxide; hydrophilicity; moieties; nuclear magnetic resonance spectroscopy; oxidation; silicon; wettability; zeolites
Abstract:
... Hydrophilic TS-1 (H-TS-1) with rich hydroxyl groups, which were confirmed by ²⁹Si and ¹H NMR techniques, exhibits much higher activities in the oxidation than conventional TS-1. This phenomenon is strongly related to the unique features of high enrichment of H₂O₂ on H-TS-1. ...
DOI:
10.1039/c3cc48220k

33. A simple access to N-(un)substituted isoquinolin-1(2H)-ones: unusual formation of regioisomeric isoquinolin-1(4H)-ones

Author:
R. Gangadhara Chary; G. Dhananjaya; K. Vara Prasad; S. Vaishaly; Y. S. S. Ganesh; Balakrishna Dulla; K. Shiva Kumar; Manojit Pal
Source:
Chemical communications 2014 v.50 no.51 pp. 6797-6800
ISSN:
1364-548X
Subject:
catalysts; chemical reactions; copper; ligands; solvents
Abstract:
... A ligand/additive/Pd-free Cu-mediated coupling/cyclization strategy afforded the first practical, one-pot and general approach towards synthesis of N-(un)substituted isoquinolin-1(2H)-ones. Both the catalyst and the solvent used are recyclable. The use of the Cu reagent in excess led to the unusual formation of regioisomeric and uncommon isoquinolin-1(4H)-ones. ...
DOI:
10.1039/c4cc01580k

34. A {0001} faceted single crystal NiS nanosheet electrocatalyst for dye-sensitised solar cells: sulfur-vacancy induced electrocatalytic activity

Author:
Yibing Li; Haifeng Wang; Haimin Zhang; Porun Liu; Yun Wang; Wenqi Fang; Huagui Yang; Ying Li; Huijun Zhao
Source:
Chemical communications 2014 v.50 no.42 pp. 5569-5571
ISSN:
1364-548X
Subject:
catalysts; catalytic activity; chemical compounds; chemical reactions; electrochemistry; nanosheets; solar cells; sulfur
Abstract:
... Hydrothermally synthesised single crystal NiS nanosheets with an exposed (0001) surface exhibited a light conversion efficiency of 8.62% as an electrocatalyst for dye-sensitised solar cells (DSSCs), significantly higher than that of Pt-based DSSCs (7.36%). The theoretical calculations revealed the exposed (0001) surface with superior catalytic activity owing to the existence of sulfur vacancies. ...
DOI:
10.1039/c4cc01691b

35. Acid- and base-functionalized core-confined bottlebrush copolymer catalysts for one-pot cascade reactions

Author:
Linfeng Xiong; Hui Zhang; Aiqing Zhong; Zidong He; Kun Huang
Source:
Chemical communications 2014 v.50 no.94 pp. 14778-14781
ISSN:
1364-548X
Subject:
catalysts; chemical reactions; composite polymers; p-toluenesulfonic acid; pyridines
Abstract:
... We demonstrate a novel method that enables the formation of core-confined bottlebrush copolymers (CCBCs) as catalyst supports. Significantly, owing to the site-isolated effect, these CCBC catalysts with the incompatible acidic para-toluenesulfonic acid (PTSA) and basic 4-(dimethylamino)pyridine (DMAP) groups can conduct a simple two-step sequential reaction in one vessel. ...
DOI:
10.1039/c4cc06573e

36. Activated carbon nanotubes: a highly-active metal-free electrocatalyst for hydrogen evolution reaction

Author:
Wei Cui; Qian Liu; Ningyan Cheng; Abdullah M. Asiri; Xuping Sun
Source:
Chemical communications 2014 v.50 no.66 pp. 9340-9342
ISSN:
1364-548X
Subject:
activated carbon; carbon nanotubes; catalysts; catalytic activity; chemical compounds; chemical reactions; durability; electrochemistry; electrolytes; hydrogen production
Abstract:
... In this communication, for the first time, we report on the development and utilization of activated carbon nanotubes (CNTs) as a highly-active metal-free electrocatalyst for the hydrogen evolution reaction (HER) with good durability in acidic electrolytes. This catalyst shows an onset overpotential and an exchange current density of 100 mV and 16.0 × 10⁻³ mA cm⁻², respectively. The possible catal ...
DOI:
10.1039/c4cc02713b

37. Activation of carbon-supported catalysts by ozonized acidic solutions for the direct implementation in (electro-)chemical reactors

Author:
C. Baldizzone; S. Mezzavilla; N. Hodnik; A. R. Zeradjanin; A. Kostka; F. Schüth; K. J. J. Mayrhofer
Source:
Chemical communications 2014 v.51 no.7 pp. 1226-1229
ISSN:
1364-548X
Subject:
catalysts; chemical compounds; chemical reactions; electrochemistry; equipment
Abstract:
... This work introduces a practical and scalable post-synthesis treatment for carbon-supported catalysts designed to achieve complete activation and, if necessary, simultaneously surface dealloying. The core concept behind the method is to control the potential without utilizing any electrochemical equipment, but rather by applying an appropriate gas mixture to a catalyst suspension. ...
DOI:
10.1039/c4cc08480b

38. Activation of oxygen evolving perovskites for oxygen reduction by functionalization with Fe–Nₓ/C groups

Author:
Rosalba A. Rincón; Justus Masa; Sara Mehrpour; Frank Tietz; Wolfgang Schuhmann
Source:
Chemical communications 2014 v.50 no.94 pp. 14760-14762
ISSN:
1364-548X
Subject:
catalysts; chemical compounds; chemical reactions; electrochemistry; electrodes; moieties; oxygen; oxygen production
Abstract:
... The incorporation of Fe–Nₓ/C moieties into perovskites remarkably activates them for the oxygen reduction reaction (ORR) and also leads to notable improvement of their activity towards the oxygen evolution reaction (OER) thus presenting a new route for realizing high performance, low cost bifunctional catalysts for reversible oxygen electrodes. ...
DOI:
10.1039/c4cc06446a

39. Advances in the environmental transmission electron microscope (ETEM) for nanoscale in situ studies of gas–solid interactions

Author:
J. R. Jinschek
Source:
Chemical communications 2014 v.50 no.21 pp. 2696-2706
ISSN:
1364-548X
Subject:
catalysts; catalytic activity; chemical compounds; chemical reactions; energy conversion; environmental protection; image analysis; nanomaterials; spectroscopy; transmission electron microscopes; transmission electron microscopy
Abstract:
... Although available since the early days of electron microscopy, recent technology developments of the environmental transmission electron microscope (ETEM) have enabled new research in the study of nanomaterials in gaseous environments. Significant improvements in scanning/transmission electron microscope (S/TEM) technologies, while containing a gaseous environment close to the object under invest ...
DOI:
10.1039/c3cc49092k

40. Allyl sulphides in olefin metathesis: catalyst considerations and traceless promotion of ring-closing metathesis

Author:
Grant A. Edwards; Phillip A. Culp; Justin M. Chalker
Source:
Chemical communications 2014 v.51 no.3 pp. 515-518
ISSN:
1364-548X
Subject:
catalysts; catalytic activity; chemical reactions; olefin; organic sulfur compounds; sulfides
Abstract:
... Allyl sulphides are reactive substrates in ruthenium-catalysed olefin metathesis reactions, provided each substrate is matched with a suitable catalyst. A profile of catalyst activity is described, along with the first demonstration of allyl sulphides as traceless promoters in relayed ring-closing metathesis reactions. ...
DOI:
10.1039/c4cc07932a

41. Amine–borane assisted synthesis of wavy palladium nanorods on graphene as efficient catalysts for formic acid oxidation

Author:
Cheng Du; Yuxiang Liao; Xing Hua; Wei Luo; Shengli Chen; Gongzhen Cheng
Source:
Chemical communications 2014 v.50 no.85 pp. 12843-12846
ISSN:
1364-548X
Subject:
catalysts; catalytic activity; electrochemistry; formic acid; graphene; nanoparticles; nanorods; oxidation; palladium; reducing agents
Abstract:
... Wavy palladium (Pd) nanorods were obtained by controlled synthesis by using amine–boranes as the reducing agents. Thanks to the unique structure and strong interaction with graphene, the as-synthesized Pd nanorods supported on graphene exhibit much enhanced electrocatalytic activity towards formic acid oxidation as compared with Pd nanoparticles. ...
DOI:
10.1039/c4cc05019c

42. Ammonium betaines: efficient ionic nucleophilic catalysts for the ring-opening polymerization of l-lactide and cyclic carbonates

Author:
Brieuc Guillerm; Vincent Lemaur; Jérôme Cornil; Roberto Lazzaroni; Philippe Dubois; Olivier Coulembier
Source:
Chemical communications 2014 v.50 no.70 pp. 10098-10101
ISSN:
1364-548X
Subject:
Lewis bases; alcohols; betaine; carbonates; catalysts; hydrogen bonding; polymerization
Abstract:
... The ionic nucleophilic character of ammonium betaine catalysts allows for controlling the ROP of l-LA for DP as high as 750 with very narrow dispersity values (≤1.18). Compared to ionic nucleophilic and hydrogen-bonding based catalysts for ROP, meta-betaine combines the positive aspects of both processes in terms of kinetics and selectivity. The versatility of ammonium betaines was evidenced by va ...
DOI:
10.1039/c4cc03347g

43. Ammonium formate decomposition over Au/TiO₂: a unique case of preferential selectivity against NH₃ oxidation

Author:
Manasa Sridhar; Daniel Peitz; Jeroen Anton van Bokhoven; Oliver Kröcher
Source:
Chemical communications 2014 v.50 no.53 pp. 6998-7000
ISSN:
1364-548X
Subject:
ammonia; ammonium; carbon dioxide; catalysts; formates; gold; oxidation; oxygen; titanium dioxide
Abstract:
... The unique selectivity of Au/TiO₂ for converting ammonium formate to CO₂ in the presence of excess O₂ and H₂O without oxidising NH₃ up to 300 °C is reported. The catalyst is highly stable and selective even after severe hydrothermal aging. ...
DOI:
10.1039/c4cc00196f

44. An air-stable cationic iridium hydride as a highly active and general catalyst for the isomerization of terminal epoxides

Author:
Nicolas Humbert; Devendra J. Vyas; Céline Besnard; Clément Mazet
Source:
Chemical communications 2014 v.50 no.73 pp. 10592-10595
ISSN:
1364-548X
Subject:
Lewis acids; aldehydes; catalysts; epoxides; hydrides; iridium; isomerization; moieties; regioselectivity; stoichiometry
Abstract:
... We describe the use of an air-stable iridium hydride catalyst for the isomerization of terminal epoxides into aldehydes with perfect regioselectivity. The system operates at low loadings of catalyst (0.5 mol%), is highly practical, scalable, and tolerates functional groups that would not be compatible with Lewis acids typically used in stoichiometric amounts. Evidence for a rare hydride mechanism ...
DOI:
10.1039/c4cc05260a

45. An amphiphilic, catalytically active, vitamin B₁₂ derivative

Author:
M. Giedyk; S. N. Fedosov; D. Gryko
Source:
Chemical communications 2014 v.50 no.36 pp. 4674-4676
ISSN:
1364-548X
Subject:
Lewis bases; assets; catalysts; chemical bonding; chemical reactions; dimethylformamide; methanol; solubility; vitamin B12
Abstract:
... We performed the reaction of vitamin B₁₂ with N,N-dimethylformamide dimethyl acetal for primary amide activation, and added MeOH as a nucleophile, to afford cobalester, the first amphiphilic cobalamin derivative. The unique combination of redox properties and solubility represents an asset for its use as a catalyst in C–C bond forming reactions. ...
DOI:
10.1039/c4cc01064g

46. An efficient oxygen evolving catalyst based on a μ-O diiron coordination complex

Author:
Yongdong Liu; Rui Xiang; Xiaoqiang Du; Yong Ding; Baochun Ma
Source:
Chemical communications 2014 v.50 no.84 pp. 12779-12782
ISSN:
1364-548X
Subject:
acetates; buffers; catalysts; chemical reactions; coordination compounds; iron; oxygen; pH
Abstract:
... A family of oxygen evolving catalysts was investigated, which was based on the most desired first-row transition metal iron. Among them, the highest turnover number of 2380 was obtained in acetate buffer at pH 4.5 with [(TPA)₂Fe₂(μ-O)(μ-OAc)]³⁺. ...
DOI:
10.1039/c4cc04118f

47. An efficient ruthenium(iv) catalyst for the selective hydration of nitriles to amides in water under mild conditions

Author:
Eder Tomás-Mendivil; Francisco J. Suárez; Josefina Díez; Victorio Cadierno
Source:
Chemical communications 2014 v.50 no.68 pp. 9661-9664
ISSN:
1364-548X
Subject:
amides; catalysts; chemical reactions; nitriles; ruthenium
Abstract:
... A Ru(iv) catalyst able to promote the selective hydration of nitriles to amides in water, at low metal loadings and under mild conditions, is presented. ...
DOI:
10.1039/c4cc04058a

48. An efficient strategy for the synthesis of polysubstituted chromeno[4,3-b]pyrrolidine derivatives

Author:
Li Tian; Guo-Qiang Xu; Yun-Han Li; Yong-Min Liang; Peng-Fei Xu
Source:
Chemical communications 2014 v.50 no.19 pp. 2428-2430
ISSN:
1364-548X
Subject:
catalysts; chemical reactions; pyrrolidines
Abstract:
... A powerful cascade reaction was developed for the synthesis of chromeno[4,3-b]pyrrolidines with high yields and excellent stereoselectivities. This efficient cascade reaction expeditiously established two fused rings which bear three contiguous stereogenic centers including one quaternary stereocenter in a single operation with low catalyst loading under mild conditions. ...
DOI:
10.1039/c3cc49504c

49. An enantioselective Diels–Alder reaction of 1,2-dihydropyridines with α-acyloxyacroleins catalyzed by a chiral primary ammonium salt

Author:
Kazuaki Ishihara; Hiroki Yamada; Matsujiro Akakura
Source:
Chemical communications 2014 v.50 no.48 pp. 6357-6360
ISSN:
1364-548X
Subject:
alkaloids; ammonium salts; catalysts; catalytic activity; cycloaddition reactions; enantioselectivity; geometry
Abstract:
... The first enantioselective Diels–Alder reaction of 1,2-dihydropyridines with α-acyloxyacroleins catalyzed by a chiral primary ammonium salt has been developed and it offers more efficient routes to key synthetic intermediates of alkaloids, for which the direct preparations were unavailable before. The asymmetric induction can be understood through the optimized geometry of an iminium salt aqua com ...
DOI:
10.1039/c4cc01445f

50. Aniline-terminated DNA catalyzes rapid DNA–hydrazone formation at physiological pH

Author:
Dylan W. Domaille; Jennifer N. Cha
Source:
Chemical communications 2014 v.50 no.29 pp. 3831-3833
ISSN:
1364-548X
Subject:
DNA; catalysts; catalytic activity; chemical compounds; chemical reactions; pH
Abstract:
... We report the effect of DNA-templation on aniline-catalyzed N-acylhydrazone formation. The reaction occurs in both two-component and three-component systems. Through systematic catalyst modifications, we are able to increase the efficiency of the DNA-templated variant to 85-fold above that of the uncatalyzed reaction at physiological pH. ...
DOI:
10.1039/c4cc00292j