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Mui Cheung

Bio: Mui Cheung is an academic researcher from Rice University. The author has contributed to research in topics: Mitsunobu reaction & Alkylation. The author has an hindex of 6, co-authored 7 publications receiving 1762 citations.

Papers
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Journal ArticleDOI
TL;DR: In this paper, 2-and 4-nitrobenzenesulfonamides are obtained from primary amines and undergo smooth alkylation by Mitsunobu reaction or by conventional methods to give N-alkylated sulfonamide in near quantitative yields.

784 citations

Journal ArticleDOI
TL;DR: In this article, 2,4-Dinitrobenzenesulfonamides can be removed without deprotecting 2,nitrobenzesulfoneamides, and a wide variety of diamines could be prepared by the combined use of these protecting/activating groups.

264 citations

Journal ArticleDOI
TL;DR: In this paper, 2-and 4-nitrobenzenesulfonamides are obtained from primary amines and undergo smooth alkylation by Mitsunobu reaction or by conventional methods to give N-alkylated sulfonamide in near quantitative yields.
Abstract: 2- and 4-Nitrobenzenesulfonamides, readily prepared from primary amines, undergo smooth alkylation by Mitsunobu reaction or by conventional methods to give N-alkylated sulfonamides in near quantitative yields. These sulfonamides could be deprotected readily via Meisenheimer complexes upon treatment with thiolates in DMF at room temperature, giving secondary amines in high yields.

42 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, a set of powerful, highly reliable, and selective reactions for the rapid synthesis of useful new compounds and combinatorial libraries through heteroatom links (C-X-C), an approach called click chemistry is defined, enabled, and constrained by a handful of nearly perfect "springloaded" reactions.
Abstract: Examination of nature's favorite molecules reveals a striking preference for making carbon-heteroatom bonds over carbon-carbon bonds-surely no surprise given that carbon dioxide is nature's starting material and that most reactions are performed in water. Nucleic acids, proteins, and polysaccharides are condensation polymers of small subunits stitched together by carbon-heteroatom bonds. Even the 35 or so building blocks from which these crucial molecules are made each contain, at most, six contiguous C-C bonds, except for the three aromatic amino acids. Taking our cue from nature's approach, we address here the development of a set of powerful, highly reliable, and selective reactions for the rapid synthesis of useful new compounds and combinatorial libraries through heteroatom links (C-X-C), an approach we call "click chemistry". Click chemistry is at once defined, enabled, and constrained by a handful of nearly perfect "spring-loaded" reactions. The stringent criteria for a process to earn click chemistry status are described along with examples of the molecular frameworks that are easily made using this spartan, but powerful, synthetic strategy.

9,069 citations

Journal ArticleDOI
TL;DR: In this paper, the authors show how in der Natur am haufigsten vorkommenden Verbindungen, so fallt auf, dass the Bildung von Kohlenstoff-Heteroatom-Bindungen gegenuber der von KHO-Kohlenstoffs-KHO-Bindingsen deutlich bevorzugt is, and das Medium naturlicher Reaktionen zumeist Wasser ist.
Abstract: Betrachtet man die in der Natur am haufigsten vorkommenden Verbindungen, so fallt auf, dass die Bildung von Kohlenstoff-Heteroatom-Bindungen gegenuber der von Kohlenstoff-Kohlenstoff-Bindungen deutlich bevorzugt ist Da zum einen Kohlendioxid die Basisverbindung der Natur ist und andererseits das Medium naturlicher Reaktionen zumeist Wasser ist, uberrascht dies sicherlich nicht Nucleinsauren, Proteine und Polysaccharide sind polymere Kondensationsprodukte kleiner Untereinheiten, die durch Kohlenstoff-Heteroatom-Bindungen verknupft sind Sogar die etwa 35 Baueinheiten, aus denen diese essentiellen Verbindungen bestehen, enthalten nicht mehr als sechs aufeinander folgende C-C-Bindungen, sieht man einmal von den drei aromatischen Aminosauren ab Mit der Natur als Vorbild richteten wir unser Interesse auf die Entwicklung leistungsfahiger, gut funktionierender und selektiver Reaktionen fur die effiziente Synthese neuartiger nutzlicher Verbindungen sowie kombinatorischer Bibliotheken mittels Heteroatomverknupfungen (C-X-C) Diese Synthesestrategie nennen wir „Click-Chemie“ Click-Chemie ist durch eine Auswahl einiger weniger nahezu idealer Reaktionen charakterisiert, mit all ihren Grenzen und Moglichkeiten In diesem Beitrag werden zum einen die strengen Kriterien, die Reaktionen erfullen mussen, um die Bezeichnung „Click-Chemie“ zu verdienen, definiert, zum anderen werden Beispiele fur molekulare Strukturen gegeben, die mit dieser spartanischen, aber dennoch leistungsfahigen Synthesestrategie leicht hergestellt werden konnen

1,380 citations

Journal ArticleDOI
TL;DR: This review concludes that Etherification without Cyclization and N-Alkylation should be considered as separate science, and the proposed treatment of Etherification with Cyclization as a separate science should be reconsidered.
Abstract: 10. Patented Literature 2616 10.1. Esterification 2616 10.2. Ether Formation 2619 10.2.1. Etherification without Cyclization 2619 10.2.2. Etherification with Cyclization 2624 10.3. N-Alkylation 2625 10.4. Other Reactions 2627 11. Summary and Outlook 2628 12. Note Added in Proof 2628 13. Abbreviations Used in This Review 2629 14. Acknowledgments 2629 15. Supporting Information Available 2630 16. References 2630

909 citations

Journal ArticleDOI
TL;DR: The similarities and differences between oxiranes and their nitrogenated analogues are summarized, concentrating on the underlying properties of aziridines and recent developments in their chemistry.
Abstract: Aziridines, the nitrogenous analogues of epoxides, have until recently excited far less interest amongst synthetic organic chemists than their oxygenated counterparts, with some justification. A range of reviews concerned with the physical properties, synthesis (asymmetric and otherwise), reactions and utility of aziridines exists; this review briefly summarizes the similarities and differences between oxiranes and their nitrogenated analogues, concentrating on the underlying properties of aziridines and recent developments in their chemistry. In addition to descriptions of the physical nature of aziridines, especially those features which underpin their utility as synthetic intermediates, the sections beneath describe reactions involving alkylative ring-opening and synthesis of aziridines.

686 citations

Journal ArticleDOI
TL;DR: Albert Isidro-Llobet, Mercedes Alvarez,* and Fernando Albericio* Institute for Research in Biomedicine, Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona, Spain this paper.
Abstract: Albert Isidro-Llobet, Mercedes Alvarez,* and Fernando Albericio* Institute for Research in Biomedicine, Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona, Spain; CIBER-BBN, Networking Centre on Bioengineering, Biomaterials and Nanomedicine, Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona, Spain; Laboratory of Organic Chemistry, Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain; and Department of Organic Chemistry, University of Barcelona, Marti i Franques 1, 08028 Barcelona, Spain Received April 28, 2008

646 citations