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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Quasi-Wittig reaction of thione-s-methylids

Pulcrano, Maria Carol 05 1900 (has links)
No description available.
2

Applications of modified Wittig reaction to butatriene synthesis

Pearson, John 01 October 1968 (has links)
The preparation of allenes by the condensation of an acyl chloride with a phosphonium ylid and subsequent elimination of an acid salt and a phosphonium oxide has been established by Bestmann and Hartung. It was felt that this process could be expanded to include the synthesis of butatrienes. Butatrienes are stabilized by aromatic substituents while aromatic substituents decrease the nucleophilicity and reactivity of the phosphonium ylids to be used in the synthesis of the butatrienes. The ylids employed were carbomethoxyphenylmethylenetriphenyl phosphorane, and a new compound, carbethoxyphenylmethylenetriphenyl phosphorane, both of which failed to form alkylated condensation products. Both ylids were prepared by the "melt" method which gave better yields than comparable processes in dry benzene. The salt of a third ylid, carbethoxyphenylmethylenetrimethylphosphonium chloride - a new compound, was also prepared. However, the process for the preparation of this salt was not consistently reproducable and gave only low yields. A previously unreported reaction involving the condensation of ethyl diethylphosphonoacetate and benzoyl chloride was carried out and led to the formation of ethyl phenylpropynoate as was proposed.
3

Stereoselective synthesis of #Beta#-hydroxycyclohexanones using the anionic oxy-cope rearrangement

Rutherford, Alistair Peter January 1999 (has links)
No description available.
4

S-block metal chemistry of iminophosphoranes, phosphonium ylides and related systems : a synthetic and structural investigation

Price, Richard D. January 1999 (has links)
This thesis details the synthesis and characterisation of s-block metal (lithium, sodium and magnesium) phosphonium ylide, R(_3)PCHR', and iminophosphorane complexes, R(_3)PNR', together with some related phosphine oxide, R(_3)PO, and sulfide, R(_3)PS, species, where R= Ph or Me(_2)N and R' = H, Me or Ph. The first three chapters of the thesis provide an introduction to the topic, with details of the experimental methods employed and results obtained. Chapter 4 presents a systematic study of Lewis base complexed s-block metal aryloxides, (ArOM L)(_2) where Ar = C(_6)H(_3)Ph(_2) or MeC(_6)H(_2)((^1)Bu)(_2), L = R(_3)PCHR', R(_3)PNR', R(_3)PO or R(_3)PS, and M = Li, Na, and (ArO)(_2)Mg(L)(_2) where Ar = MeC(_6)H(_2)(^1)Bu)(_2) and L = R(_3)PCHR’ or R(_3)PNR'. This includes a discussion of the single crystal XRD structures of the eight neutral ligands used, L, and ten new complexes containing either lithium or sodium. Chapter 5 describes the application of some related s-block metal ylide complexes, e.g. Ph(_3)PCHMe-LiN(CH(_2)Ph(_2))(_2) and Ph(_3)PCHMe-NaN(SiMe(_3))(_2), to the Wittig reaction, together with some solution-state and solid-state discussions (two single crystal XRD structures) of s-block metal amide-phosphonium ylide complexes, R(_3)PCHR'.MNR'(_2) where R = Ph or Me(_2)N, R’ = H or Me, and R" = SiMe(_3) or CH(_2)Ph Chapter 6 details a range of N-s-block metallated iminophosphorane complexes (e.g. Ph(_3)PNLi-LiBr.2thf and R(_3)PNMgX-L where R = Ph or Me(_2)N and L = Lewis base) their application to transmetallation reactions with copper(I) compounds, solution-state and solid-state NMR studies and six new single- crystal XRD structures. Chapter 7 describes some very recent work involving alkyldiphenylphosphonium ylides, MePh(_2)PCHPh, and imines, MePh(_2)PNPh, including a single crystal XRD structural study of the latter and three of its lithium derivatives, e.g. [CH(_2)LiPh(_2)PNPh](_4). Chapter 8 is concerned with a number of unexpected results, including the synthesis, solid-state structure and proposed mechanism of a novel A^-phosphino- iminophosphorane, Ph(_2)(C(_3)H(_4)Ph)PNP(C(_3)H(_5))Ph, and two aminophosphonium salts, [R(_3)PNH(_2)](^+)[OC(_6)H(_3)Ph(_2)]" where R = Ph or Me(_2)N.
5

Aspects of enol-y- lactone chemistry : approaches towards the synthesis of a [beta]-furanosesquiterpene

Price, Martyn Frederick. January 1980 (has links) (PDF)
Photocopy of typescript
6

Development of polymeric reagents for Wittig reactions

Leung, Shu-wai., 梁樹偉. January 2010 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy
7

Aspects of enol-y- lactone chemistry : approaches towards the synthesis of a [beta]-furanosesquiterpene / by Martyn Frederick Price

Price, Martyn Frederick January 1980 (has links)
Photocopy of typescript / v, 182 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Organic Chemistry, 1981
8

Aspects of enol-y- lactone chemistry : approaches towards the synthesis of a [beta]-furanosesquiterpene /

Price, Martyn Frederick. January 1980 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Dept. of Organic Chemistry, 1981. / Photocopy of typescript.
9

Methodological and mechanistic studies of the Wittig reaction

Peterson, Matthew John. January 1992 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1992. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
10

Biosynthetic studies of strobilurins

Soares-Sello, Anna Mampe January 1997 (has links)
No description available.

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