• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 7043
  • 2586
  • 910
  • 798
  • 313
  • 280
  • 280
  • 280
  • 280
  • 280
  • 279
  • 150
  • 132
  • 130
  • 103
  • Tagged with
  • 18714
  • 8837
  • 3070
  • 2037
  • 1655
  • 1329
  • 1195
  • 995
  • 930
  • 870
  • 816
  • 815
  • 815
  • 773
  • 696
  • 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.
171

THE DIMER OF 1,3-DIPHENYL-1,3-BUTADIENE

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 19-03, page: 0445. / Thesis (Ph.D.)--The Florida State University, 1958.
172

THE KINETICS OF THE CYCLOPROPYLCARBINYL REARRANGEMENT

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 21-08, page: 2115. / Thesis (Ph.D.)--The Florida State University, 1960.
173

STUDIES IN THE CHEMISTRY AND SPECTRA OF ARYL BORANES

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 23-05, page: 1519. / Thesis (Ph.D.)--The Florida State University, 1962.
174

THE REACTION OF TRIVALENT ORGANOPHOSPHORUS COMPOUNDS WITH COVALENT AZIDES

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 27-08, Section: B, page: 2660. / Thesis (Ph.D.)--The Florida State University, 1966.
175

A STUDY OF THE HALLER-BAUER CLEAVAGE OF AN OPTICALLY ACTIVE CYCLOPROPYL KETONE

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 20-08, page: 3073. / Thesis (Ph.D.)--The Florida State University, 1959.
176

THE HYDROLYSIS OF FIVE-MEMBERED CYCLIC IMIDES AND POLYIMIDES

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 25-04, page: 2231. / Thesis (Ph.D.)--The Florida State University, 1964.
177

THE DECARBOXYLATION TEMPERATURES OF BRIDGEHEAD BETA-KETO ACIDS IN SMALL BICYCLIC RING SYSTEMS

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 25-12, page: 6964. / Thesis (Ph.D.)--The Florida State University, 1964.
178

FREE RADICAL INDUCED DECOMPOSITION OF ARYL AZIDES

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 28-07, Section: B, page: 2768. / Thesis (Ph.D.)--The Florida State University, 1967.
179

THE THERMODYNAMICS OF THE LANTHANIDE WITH ORGANIC ACIDS

Unknown Date (has links)
The thermodynamic parameters ((DELTA)G, (DELTA)H & (DELTA)S) of the formation of the europuim monooxalate complex has been determined at 25(DEGREES)C and 0.1M ionic strength (NaClO(,4)) by means of solvent extraction. (DELTA)G values show that the 5-membered oxalate ring is more stable than those of longer chain aliphatic dicarboxylates (malonate, succinate, glutarate or adipate). This effect is reflected in the complexation entropy values, (DELTA)S(,101). / The stability constants for trivalent Eu complexes with benzene polycarboxylates (trimellitate, hemimellitate and pyromellitate) were measured using a solvent extraction system at 25(DEGREES)C and 0.1M ionic strength (NaClO(,4)). The values measured at varying hydrogen ion concentrations show that either protonated species do not form or their formation constants are not significant enought to influence the overall observed conditional constants. The enthalpies for lanthanide hemimellitate and pyromellitate were determined by calorimetric titration. / Solvent extraction studies were conducted for Eu and Am complexes with mellitate at 0.1M and 2.0M (NaClO(,4)). In this case the stability constants for protonated species, MHL and MH(,2)L, were determined. The effective charges calculated from the experimental free energy values of these polycarboxylates indicate a significant charge polarization in the ligand which could be induced through inductive and/or resonance effects. / Source: Dissertation Abstracts International, Volume: 46-06, Section: B, page: 1918. / Thesis (Ph.D.)--The Florida State University, 1985.
180

STEREOSELECTIVE TRANSFORMATIONS OF CHIRAL IRON COMPLEXES

Unknown Date (has links)
A study of the reactivity of transition metal acyl enolates, in particular enolates of a chiral iron acyl complex, CpFe(CO)(PPh(,3))(COCH(,3)), has been undertaken. Concurrent with the above study has been the study of methods for the recovery of functionalized transition metal acyl ligands after enolate reaction. These recovered acyl ligands were found to have a defined relative stereochemistry at new chiral centers formed under the chiral iron atom's influence. A survey of reactivity with a variety of electrophiles was undertaken for a variety of transition metal acyl enolates. The types of reactions encompassed included enolate alkylations, stereoselective aldol and imine condensations, and condensations wtih nitrones and epoxides. The positively charged counterion associated with a transition metal acyl enolate was found to influence both the reactivity and stereoselectivity of the enolate in its reactions with prochiral substrates. The acyl ligands in transition metal acyl enolate alkylation products could be cleaved to esters, the aldol products cleaved to beta-hydroxy esters, and the imine condensation products converted into beta-lactams. A conjugate addition/alkylation sequence involving chiral alpha, beta unsaturated iron acyl complexes was also discovered. In this reaction, two new chiral centers were formed stereoselectively under the influence of the chiral iron in one reaction. The elaborated acyl ligands in these complexes could then be easily convered into single diastereomers of cis-disubstituted beta-lactams when primary amine anions were used for the conjugate addition, or erythro carboxylic acids when alkyl lithiums were used for the conjugate addition. / Source: Dissertation Abstracts International, Volume: 46-08, Section: B, page: 2674. / Thesis (Ph.D.)--The Florida State University, 1985.

Page generated in 0.036 seconds