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001 ocn810191447;

003 OCoLC;

005 20141212032704.0;

006 m d ;

007 cr bn|||||||||;

008 120918s2012 ncua ob 000 0 eng d;

035 a| (Sirsi) o810191447;

035 a| (OCoLC)810191447;

049 a| EREE;

090 a| QD181.Z7;

100 1 a| Harris, Caleb F.?| UNAUTHORIZED;

245 10 a| Synthesis and reactions of novel heteroarylzirconocene reagents /c| by Caleb F. Harris.;

260 a| [Greenville, N.C.] :b| East Carolina University,c| 2012.;

300 a| 71 pages :b| illustrations (some color), digital, PDF file;

336 a| text2| rdacontent;

337 a| computer2| rdamedia;

338 a| online resource2| rdacarrier;

538 a| System requirements: Adobe Reader.;

538 a| Mode of access: World Wide Web.;

502 b| M.S.c| East Carolina Universityd| 2012.;

500 a| Presented to the faculty of the Department of Chemistry.;

500 a| Advisor: Shouquan Huo.;

500 a| Title from PDF t.p. (viewed Oct. 12, 2012).;

520 3 a| The cross-coupling of metallated heteroaromatic species with aryl and heteroaryl halides is a powerful and highly desirable transformation in both the synthesis of pharmaceutical compounds as well as materials development. However, current methodology in this area has some limitations, particularly with organometallic reagents derived from 2-halopyridines, 2-haloquinolines, and other similar heteroaromatic compounds. Suzuki cross-coupling reactions of 2-pyridyl boronic acids or esters is often reported to be low yielding due to protodeborylation. In particular, the preparation of the corresponding heteroaromatic boronic reagents is often associated with low yields. Although Negishi cross-coupling reactions are often reported to be high yielding, the generation of heteroaromatic Negishi reagents require the use of expensive and user unfriendly Rieke® Zinc. The Stille reaction is the least desirable because of the highly toxic tin waste streams generated. Zirconium is a non-toxic, inexpensive, and abundant metal that exists primarily in the Zr(IV) oxidation state and its application in organic synthesis has been extensively studied. However, the preparation of heteroaromatic zirconocene reagents and their application in organic synthesis have not been reported. In 1986, Negishi reported the generation of a Zr(II) species, in situ, by reacting Cp₂Zr(IV)Cl₂ with 2 equivalents of n-BuLi followed by a [beta]-H abstraction process. We anticipated that the oxidative addition of a heteroaromatic halide to the Negishi reagent, "Cp₂Zr(II)", would generate the desired heteroaromatic zirconocene reagents. These novel reagents were successfully generated and used in palladium-catalyzed cross-coupling reactions.;

504 a| Includes bibliographical references.;

650 0 a| Zirconium.=| ^A87678;

650 0 a| Chemical tests and reagents.=| ^A45160;

650 0 a| Organic compoundsx| Synthesis.=| ^A1214;

650 0 a| Halides.=| ^A605248;

653 a| Chemistry;

700 1 a| Huo, Shouquan.?| UNAUTHORIZED;

710 2 a| East Carolina University.b| Department of Chemistry.?| UNAUTHORIZED;

856 40 z| Access via ScholarShipu| http://hdl.handle.net/10342/4004;

949 o| jgml;

994 a| C0b| ERE;

596 a| 1 4;

998 a| 3108481;

999 a| CLICK ON WEB ADDRESSw| ASISc| 1i| 3108481-1001l| JNETm| JOYNERr| Ys| Yt| JNE3ETDu| 9/18/2012x| ETDz| JERESOURCE;

999 a| CLICK ON WEB ADDRESSw| ASISc| 1i| 3108481-2001l| HSLELECm| HSLr| Ys| Yt| HEETDu| 9/18/2012x| ETDz| HERESOURCE;

Synthesis and reactions of novel heteroarylzirconocene reagents / by Caleb F. Harris.

Author/creator	Harris, Caleb F.
Other author	Huo, Shouquan.
Other author	East Carolina University. Department of Chemistry.
Format	Theses and dissertations
Publication Info	[Greenville, N.C.] : East Carolina University, 2012.
Description	71 pages : illustrations (some color), digital, PDF file
Supplemental Content	Access via ScholarShip
Subjects	Zirconium. Chemical tests and reagents. Organic compounds--Synthesis. Halides.

Summary	The cross-coupling of metallated heteroaromatic species with aryl and heteroaryl halides is a powerful and highly desirable transformation in both the synthesis of pharmaceutical compounds as well as materials development. However, current methodology in this area has some limitations, particularly with organometallic reagents derived from 2-halopyridines, 2-haloquinolines, and other similar heteroaromatic compounds. Suzuki cross-coupling reactions of 2-pyridyl boronic acids or esters is often reported to be low yielding due to protodeborylation. In particular, the preparation of the corresponding heteroaromatic boronic reagents is often associated with low yields. Although Negishi cross-coupling reactions are often reported to be high yielding, the generation of heteroaromatic Negishi reagents require the use of expensive and user unfriendly Rieke® Zinc. The Stille reaction is the least desirable because of the highly toxic tin waste streams generated. Zirconium is a non-toxic, inexpensive, and abundant metal that exists primarily in the Zr(IV) oxidation state and its application in organic synthesis has been extensively studied. However, the preparation of heteroaromatic zirconocene reagents and their application in organic synthesis have not been reported. In 1986, Negishi reported the generation of a Zr(II) species, in situ, by reacting Cp₂Zr(IV)Cl₂ with 2 equivalents of n-BuLi followed by a [beta]-H abstraction process. We anticipated that the oxidative addition of a heteroaromatic halide to the Negishi reagent, "Cp₂Zr(II)", would generate the desired heteroaromatic zirconocene reagents. These novel reagents were successfully generated and used in palladium-catalyzed cross-coupling reactions.
General note	Presented to the faculty of the Department of Chemistry.
General note	Advisor: Shouquan Huo.
General note	Title from PDF t.p. (viewed Oct. 12, 2012).
Dissertation note	M.S. East Carolina University 2012.
Bibliography note	Includes bibliographical references.
Technical details	System requirements: Adobe Reader.
Technical details	Mode of access: World Wide Web.

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Synthesis and reactions of novel heteroarylzirconocene reagents / by Caleb F. Harris.

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