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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

Synthetic studies towards gelsemine

Bainbridge, Jeremy D. E. January 1997 (has links)
No description available.
2

Synthesis of 3,4-disubstituted furans and 3-substituted furans using 3,4-bis(tri-n-butylstannyl)furan and 3-(tri-n-butylstainnyl)furan as building blocks.

January 1993 (has links)
by Yun Yang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 111-118). / Acknowledgements --- p.i / Contents --- p.ii / Abstract --- p.v / List of Acronyms and Abbreviations --- p.vi / Chapter Chapter 1. --- Introduction / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Reactions of Furans / Chapter 1.2.1 --- Electrophilic Substitution --- p.3 / Chapter 1.2.2 --- Nucleophilic Substitution --- p.6 / Chapter 1.2.3 --- Addition Reaction --- p.9 / Chapter 1.2.4 --- Oxidation Reaction --- p.9 / Chapter 1.3 --- Review of Synthetic Methods for the Syntheses of Polysubstitued Furans --- p.11 / Chapter 1.3.1 --- "From 1,4-Dicarbonyl Compounds" --- p.11 / Chapter 1.3.2 --- From α-Haloketones --- p.12 / Chapter 1.3.3 --- From Hetero Diels-Alder and Retro-Diels-Alder Reactions --- p.15 / Chapter 1.3.4 --- From Alkynes / Chapter 1.3.4.1 --- Via Radical Cyclization --- p.16 / Chapter 1.3.4.2 --- Via Insertion of Isocyanides --- p.16 / Chapter 1.3.4.3 --- Via Addition of Carbenoids --- p.17 / Chapter 1.3.4.4 --- Via Pd-Catalyzed Addition and Cyclization Reactions --- p.19 / Chapter 1.3.5 --- FromAllenes / Chapter 1.3.5.1 --- Via Allenic Sulfonium Salts --- p.20 / Chapter 1.3.5.2 --- Via Rh or Ag Catalyzed Cyclization --- p.21 / Chapter 1.3.5.3 --- Via Acylium Ions Addition to Allenylsilanes --- p.21 / Chapter 1.3.5.4 --- Via Allenic Palladium Intermediates --- p.22 / Chapter 1.3.6 --- From Pyrylium Salts --- p.23 / Chapter 1.3.7 --- From Miscellaneous Sources --- p.24 / Chapter 1.4 --- "Review of Synthetic Methods for the Syntheses of 3,4-Disubstituted Furans" / Chapter 1.4.1 --- From Functionalization of Furan Ring --- p.25 / Chapter 1.4.1.1 --- "Modification of Diethyl Furan-3,4-dicarboxylate" --- p.25 / Chapter 1.4.1.2 --- Modification of 3-(Hydroxymethyl)furan --- p.27 / Chapter 1.4.1.3 --- "From Boroxines Derived from 3,4-Bis(trimethylsilyl)furan…" --- p.28 / Chapter 1.4.2 --- From Ylide --- p.29 / Chapter 1.4.3 --- "From 2-Butyne-l,4-diol" --- p.29 / Chapter 1.4.4 --- From Hetero Diels-Alder and Retro-Diels-Alder Reactions --- p.30 / Chapter 1.4.5 --- From Sulfolene --- p.31 / Chapter 1.5 --- Aim of the Present Work --- p.32 / Chapter Chapter 2. --- Results and Discussion / Chapter 2.1 --- "Synthesis of 3,4-Bis(tri-n-butylstannyl)furan (47) and 3-(Tri-n-butylstannyl)furan (48) from Bis(tri-n-butylstannyl)acetylene (49) and 4-Phenyloxazole (50)" --- p.34 / Chapter 2.2 --- Stille-type Palladium-catalyzed Cross-coupling Reactions with Various Organic Halides --- p.36 / Chapter 2.2.1 --- General Features of Stille's Reaction --- p.38 / Chapter 2.2.2 --- Solvents and Catalysts --- p.42 / Chapter 2.2.3 --- Isolation and Purification of Products --- p.45 / Chapter 2.2.4 --- Direct Coupling with Organic Halides --- p.45 / Chapter 2.2.4.1 --- Acid Chloride --- p.46 / Chapter 2.2.4.2 --- Aryl Halide --- p.51 / Chapter 2.2.4.3 --- Vinyl Halide --- p.53 / Chapter 2.2.4.4 --- Allylic Bromide --- p.53 / Chapter 2.2.4.5 --- Benzylic Halide --- p.54 / Chapter 2.2.5 --- Mechanistic Aspects / Chapter 2.2.5.1 --- Mechanism for the Stille's Reaction of Acid Chloride --- p.54 / Chapter 2.2.5.2 --- Mechanism for the Stille's Reaction of Aryl Halide --- p.56 / Chapter 2.2.6 --- Carbonylative Coupling --- p.59 / Chapter 2.2.7 --- Conclusion --- p.64 / Chapter 2.3 --- "Synthesis of Unsymmetrical 3,4-Disubstituted Furans via Lithiation of 3,4-Bis(tri-n-butylstannyl)furan (47)" / Chapter 2.3.1 --- Lithiation of Organotin Compounds: General Remarks --- p.65 / Chapter 2.3.2 --- "Lithiation of 3,4-Bis(tri-n-butylstannyl)furan (47) with n-BuLi" --- p.68 / Chapter 2.3.3 --- Trapping of 3-Lithium-4-(tri-n-butylstannyl)furan (63) with Electrophiles --- p.70 / Chapter 2.3.4 --- "Synthesis of Unsymmetrical 3,4-Disubstituted Furans from 3-Substituted-4-(tri-n-butylstannyl)furan (64) via Stille's Reactions" --- p.72 / Chapter 2.3.5 --- Conclusion --- p.75 / Chapter 2.4 --- Halogenation --- p.75 / Chapter Chapter 3. --- Application to Natural Product Synthesis / Chapter 3.1 --- "Synthesis of a Key Intermediate in the Total Synthesis of (20,S)-Camptothecin" --- p.79 / Chapter 3.2 --- Synthesis of an Analog of Lactaral --- p.80 / Experimental --- p.83 / References --- p.111 / Appendix --- p.119
3

Diazetines, diazetidines, and mechanisms of the ene reaction

Seymour, Catherine Ann January 1982 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE / Vita. / Includes bibliographical references. / by Catherine Ann Seymour. / Ph.D.
4

Preparation and reactions of Diels-Alder adducts of lignin-derived quinones

Wozniak, John C. 11 June 1988 (has links)
No description available.
5

A synthetic approach to Yuehchukene analogues /

Chan, Tin-yau. January 1987 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1987.
6

The steroelectivity of chiral allenes in the dielsalder reaction

Herring, Laura Elizabeth 12 1900 (has links)
No description available.
7

Regiochemistry and stereochemistry of the Diels-Alder reaction; the synthesis and reactions of 1,3-cyclohexadienes

Duckwall, Louis Ralph 12 1900 (has links)
No description available.
8

Synthesis of polysubstituted pyridines : Diels-Alder addition of 1-AZA-1, 3-dienes with acetylenic and ethylenic dienophil

Steizer, Lindsay S. January 1986 (has links)
The synthesis of methyl 3,6-dimethylpyridine-2-carboxylate (192) by the Diels-Alder addition of 3-butene-2-one dimethylhydrazone (190) and methyl-2-butynoate (16) is described. The structure of 192 was confirmed by the synthesis of methyl 2,6-dimethylpyridine-3-carboxylate (195), the opposite regioisomer.The synthesis of methyl 3,5-dimethylpyridine-2-carboxylate (199) from [4+2] cycloaddition of 2-methyl-2-propenal dimethylhydrazone (171) and 16 is described. In addition to producing a small amount of 199 directly, the reaction produced an intermediate of possible structure 198 which yielded 199 on catalytic dehydrogenation.On prolonged heating, 2-acetyl-5-methylpyridine (200) was produced by the reaction of diene 171 with methyl vinyl ketone (176).The preparation of 2-cyan-5-methylpyridine (201) from the tetrahydropyridine derivative 175 via catalytic dehydrogenation is described.The synthesis of 5,7-dioxo-3-methyl-6-phenyl-1,1.,5,6,7-pentahydropyrroloC3,1.-b] pyridine (202) through the Diels-Alder addition of diene 171 and N-phenylmaleimide (149) is described. Also reported is the preparation of 5,7-dioxo-3-methyl-6-phenyl-3,5,6-trihydropyrrolo [3,1+-b]pyridine (203) via dehydrogenation of 202. / Department of Chemistry
9

An approach to carbocyclic analogues of C-nucleosides.

Reader, Grant William. January 1973 (has links)
No description available.
10

The chemistry of benzophosphole derivatives /

Nwe, Khin Than January 1974 (has links)
No description available.

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