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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

SPONTANEOUS REACTIONS AND NEW COPOLYMERS FROM ELECTRON DEFICIENT, HIGHLY SUBSTITUTED OLEFINS.

RIGHETTINI, ROBIN FRANCIS. January 1985 (has links)
The experimental results of the current work have three parts. First, the synthesis and characterization of several new copolymers by the free-radical copolymerization between several highly substituted electron-deficient olefins and furan, benzofuran, indene, alphamethylstyrene, and divinyl ether is discussed. Electron-poor olefins used included dimethyl cyanofumarate, carbomethoxymaleic anhydride and tricarbomethoxyethene. The spontaneous reactions of these monomer pairs were also investigated in both bulk and solution. Second, the effect of synthesis temperature on the composition of the previously reported (co)polymers of styrene with tricarbomethoxyethene and dimethyl dicyanofumarate are given. A ceiling temperature for the synthesis of this copolymer was found to be 220°C. Attempted copolymerization of tetracarbomethoxyethene gave evidence of a small but detectable amount of reaction. Finally, detailed procedures for the synthesis of dimethyl cyanofumarate, carbomethoxymaleic anhydride and tricarbomethoxyethene are given, including a new synthesis of carbomethoxymaleic anhydride.
2

PROPERTIES AND REACTIVITY OF ELECTROPHILIC OLEFINS AND QUINODIMETHANES.

CRAMER, RANDALL JOHN. January 1982 (has links)
This work involves a three part study concerning the synthesis and reactivity of quinodimethanes, the determination of reduction potentials of electrophilic olefins, and the crystal structure determination of a new charge transfer complex. Treatment of p-xylylene dicyanide (10) with NaH and dimethyl carbonate in glyme yielded a,a'-bis(methoxycarbonyl)-p-xylylene dicyanide (11a), 82% yield. Oxidation of 11a with N-chlorosuccinimide and triethyl amine in acetonitrile at 0° gave 7,8-di(methoxycarbonyl)-7,8-dicyanoquinodimethane (12a), 64% yield, d. 268°. This quinodimethane homopolymerizes spontaneously and forms a Wurster complex with tetramethyl-p-phenylenediamine and a blue-black CT-complex with tetrathiafulvalene. Cyclic voltammetry reduction potentials (E^(Red)(,p)) UV absorptions and ¹H-NMR chemical shift data of 22 olefins compounds were measured. The sequence for the ability to stabilize the ethylenic radical anion was found to be (diagram omitted) > -CN >-CO₂CH₃ > Cl > Br > H as expected. An inverse relationship between chemical reactivity and reduction potential was found for tetramethyl ethylenetetracarboxylate (25) and the triester derivative (33). Although 25 has a lower E^(Red)(,p) (-1.30v) than 33, it is less reactive toward polymerization. A linear correlation of E^(Red)(,p) and Hammett substituent constants was seen for the substituted maleic anhydrides and cyanofumarates. No correlations were seen for sterically crowded derivatives of 33. The crystal structure of tetrathiafulvalinium dimethyl dicyanofumarate was determined from a single crystal X-ray study. The crystal belongs to the monoclinic space group P2₁/C with two complexes per unit cell with cell constants a = 11.075(2) Å, b = 11.615(3) Å, c = 6.623(4) Å, α = 95.7°(16), V = 847.6(9) ų. The structural parameters have been refined to convergence, R = 0.0492 and R(,w) = 0.0614.
3

Anodic oxidation induced [2+2] carbon-carbon coupling reactions of terminal alkenes using organo-Re(II) electron transfer mediator / Anodic oxidation induced [two plus two] carbon-carbon coupling reactions of terminal alkenes using organo-Re(II) electron transfer mediator

May, Joshua Paul 14 December 2015 (has links)
Access to abstract restricted until 12/14/2015. / Access to thesis restricted until 12/14/2015. / Department of Chemistry

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