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-exchange membranes constitute a promising tool which, when used properly, can be applied in the synthesis of ionic compounds used in chemical and other industries. An interest in application of electrodialysis for chemical synthesis has grown, recently, which has resulted in an increasing number of scientific papers. The intention of this review is to provide a summary on the applicability of ion-exchange membranes and the prospects of electrodialysis-based processes in chemical synthesis. 2 Ion-exchange membranes The most widely used IEMs consist of polymeric resins with attached

6430 4 [47] Omachi H, Segawa Y, Itami K. Synthesis and racemization process of chiral carbon nanorings: a step toward the chemical synthesis of chiral carbon nanotubes. Org Lett 2011;13:2480–3. 21486080 10.1021/ol200730m Omachi H Segawa Y Itami K. Synthesis and racemization process of chiral carbon nanorings: a step toward the chemical synthesis of chiral carbon nanotubes Org Lett 2011 13 2480 3 [48] Hitosugi S, Nakanishi W, Yamasaki T, Isobe H. Bottom-up synthesis of finite models of helical (n,m)-single-wall carbon nanotubes. Nat Commun 2011;2:492. 10.1038/ncomms

Pure &App/. Chern., Vol. 70, No. 2, pp. 407-410, 1998. Printed in Great Britain. Q 1998 IUPAC Chemical synthesis of oligosaccharide mimetics Pierre Sinay Ecole Normale Supkrieure, Dkpartement de Chimie, URA CNRS 1686 24, Rue Lhomond, 75231 Paris Cedex 05, France Abstract : A variety of C-disaccharides have been selectively and expeditiously synthesized through the so-called tether approach. Jntroduction . 'Oligosacch&ides are involved in a increasing number of biological processes. This has stimulated the development of selective methods for the

Yasutomo Segawa, Akiko Yagi and Kenichiro Itami 3 Chemical Synthesis of Cycloparaphenylenes 3.1 Introduction Since carbon nanotubes (CNTs) were first discovered by Iijima in 1991 [1], the synthe- sis of CNTs has attracted the interest of many scientists because of their outstanding physical properties as well as their potential applications in technology [2–7]. Sin- gle-walled CNTs can be considered as rolled-up structures of graphene sheets. The manner in which the graphene sheet is wrapped is given by the chiral index, which is represented by a pair of

of (5,5) CNT template 3 with benzyne, generated from o -trimethylsilylphenyl triflate and Bu 4 NF. Surface-catalyzed growth strategy It was always our ambition to develop methods for the chemical synthesis of CNTs from hemispherical polyarenes that rely entirely on metal-free organic reactions, such as those described above. As a backup plan, however, we knew that CNTs could be grown on nanoparticles of catalytically active metals [ 3 ] and hypothesized that attachment of hemispherical polyarenes to such metal surfaces should lead to the preprogramed growth of

Abstract

Due to the unique properties of graphene, single layer, bilayer or even few layer graphene peeled off from bulk graphite cannot meet the need of practical applications. Large size graphene with quality comparable to mechanically exfoliated graphene has been synthesized by chemical vapor deposition (CVD). The main development and the key issues in controllable chemical vapor deposition of graphene has been briefly discussed in this chapter. Various strategies for graphene layer number and stacking control, large size single crystal graphene domains on copper, graphene direct growth on dielectric substrates, and doping of graphene have been demonstrated. The methods summarized here will provide guidance on how to synthesize other two-dimensional materials beyond graphene.

935 Pure Appl. Chem., Vol. 78, No. 5, pp. 935–945, 2006. doi:10.1351/pac200678050935 © 2006 IUPAC Green chemistry: The development of cross-dehydrogenative coupling (CDC) for chemical synthesis* Chao-Jun Li‡ and Zhiping Li Department of Chemistry, McGill University, 801 Sherbrooke St. West, Montreal, Quebec, H3A 2K6, Canada Abstract: Social, economic, and environmental concerns about chemical production have been increasing. These concerns all originate from the inefficiency of conventional chemical syntheses. On the basis of the “E-factor”, a concept of the

reactive nature of radicals [ 6 ]. Microfluidics, known for its precise handling of fluid hydrodynamics [ 7 ], turns out to be an ideal tool to control the radical diffusion at the interface between the plasma and the liquid. In this study, a plasma integrated microfluidics device has been developed for chemical synthesis. The transfer of reactive species (especially radicals) from the gas phase to the liquid phase is tuned by the multiphase flow. A high transfer efficiency is ensured by the high surface/volume ratio of plasma bubbles. Yamanishi et al. [ 8 ] presented a

CHEMICAL SYNTHESIS OF OLIGO- AND POLYNUCLEOTIDES F. CRAMER Max-Planck-Institut für experimentelle Medizin, Chemische Abteilung, Gö"ttingen, Germany INTRODUCTION Genetics, a subject with diverse aspects, is here treated from the nucleic acid chemist's point of view, since nucleic acid chemists have contributed and still can contribute a great deal to the problern of genetic information, genetic transcription, and regulation (Figure 1). Synthetic polynucleotides of known composition and known sequence in many cases allow definition of a problern more

Chemical Synthesis of Tropoyl Coenzyme A Georg G. Gross and Karl J. Koelen Abteilung Allgemeine Botanik, Universität Ulm, Oberer Eselsberg, D-7900 Ulm Z. Naturforsch. 35 c, 363-366 (1980); received March 10, 1980 Tropoyl Coenzyme A, Thioester, Tropoyl N-Hydroxysuccinimide Ester Tropoyl coenzyme A has been synthesized in good yields via the corresponding N-hydroxysuc- cinimide ester. The UV-spectrum of the purified thioester has an absorption maximum at 257 nm; at this wavelength, a molar extinction coefficient of 19.2 x 106 [cm2 mol-1] has been determined