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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.
11

Kinetics and mechanism of substitution reactions of tungsten carbonyl complexes containing bidentate sulfur ligands

Schultz, Linda D. 12 1900 (has links)
Previous investigation of the kinetics and mechanism of the substitution reaction of bidentate substituted transition metal carbonyl complexes with Lewis bases (L') to yield the cis distributed bidentate substitution product, where M=Cr, Mo, or W and S-S = DTO (2,2,7,7-tetra-methyl-3, 6-dithiaoctane) or DTN (2,2,8,8-tetramethyl-3,7-dithianonane) have suggested that this reaction proceeds via a mechanism involving initial reversible dissociation of one end of the bidentate sulfur ligand followed by rapid attack of L' on the resulting five-coordinate intermediate.
12

Nickel(II) complexes of a phosphorus-nitrogen macrocyclic ligand; palladium(II) and nickel(II) complexes of polydentate ligands containing phosphorus and sulfur /

Nappier, Jeanette Riker January 1973 (has links)
No description available.
13

Electrochemical investigation of transition metal complexes of quadridentate macrocyclic ligands/

Tokel, Nurhan Elias,1942- January 1970 (has links)
No description available.
14

Cobalt(III) and palladium(II) complexes of polydentate ligands containing Group V-A donor atoms /

Kordosky, Gary Alan January 1971 (has links)
No description available.
15

Nickel(II) complexes of a phosphorus-nitrogen macrocyclic ligand; palladium(II) and nickel(II) complexes of polydentate ligands containing phosphorus and sulfur /

Nappier, Jeanette Riker January 1973 (has links)
No description available.
16

Synthesis and characterization of new tetraaza, tetraene, macrocyclic ligands and their metal complexes /

Riley, Dennis Patrick January 1975 (has links)
No description available.
17

Chiral phosphine synthesis by the application of directed metallation

Lin, Qinghong, Chemistry, Faculty of Science, UNSW January 1999 (has links)
The ortho metallation of some aromatic ring systems has been investigated in regard to the influence of several types of phosphorus-centred directing groups upon the reactivity, regioselectivity, and utility in later synthetic elaboration. The metallation step allows derivatisation in several useful ways, offering several routes to the synthesis of novel chiral ditertiary phosphines. Thus, an ortho lithiation of N,N,N',N'-tetramethyl-P-phenylphosphonic diamide (10) led to the interesting primary phosphine, 2-(diphenylphosphino)phenylphosphine (14), after elaboration of the phosphonic diamide directing group. This primary phosphine undergoes an unprecedented facile phenyl group exchange process between its two phosphorus atoms, upon di-lithiation of the primary phosphorus centre. The primary phosphorus centre of (14) has been elaborated in several ways to yield new ditertiary phosphines. The alkylation of this centre in the copper(I) chelate complex has been investigated in several directions. In another direction, (14) has been chemically elaborated to give a new hybrid chiral ditertiary phosphine ligand, &quotSemiPHOS&quot, containing both a chiral phospholane ring and an adjacent diphenylphosphino group. SemiPHOS has been obtained in optically pure forms by a stereoselective synthesis and, independently, by a resolution procedure on its racemate. The molecular design of SemiPHOS was devised such that, when chelated to a metal atom, a subtle steric interaction appears to allow the chirality of the phospholane ring to influence the neighbouring diphenylphosphino group to adopt a complementary chiral conformation. This idea was tested and evaluated by applying SemiPHOS in catalytic asymmetric hydrogenations of (Z)-a-(Nacylamino) acrylate substrates to produce the R-amino acid precursors. Aryl species lithiated ortho to phosphorus-centred directing groups were coupled oxidatively by a convenient in situ method, to yield biaryl species that could then be elaborated to give biaryl ditertiary phosphine ligands. This method was used to make several atropisomeric chiral ditertiary phosphines.
18

Syntheses and reactivities of some cyanophosphine ligands

Saval, Ivan Harmodio 03 June 2011 (has links)
The ligands o-cyanophenyl(diphenyl)phosphine and bis(dimethylamino)(o-cyanophenyl) phosphine were synthesized from o-bromobenzonitrile and diphenylchlorophosphine and bis(dimethylamino)chlorophosphine, respectively. Both ligands were identified by IR, NMR and physical constant data. The reaction of bis(dimethylamino)(o-cyanophenyl)phosphine with sulfur or CH3I yields complexes of the stoichiometry [(CH3)2N]2(o-C6H4CN)P(X) (X=S, CH3I). NMR and IR spectral data suggest that the phosphorus is the site of reaction.Reaction of 2-cyanocyclohexyl(diphenyl)phosphine, 2-cyanocyclopentyl(diphenyl)phosphine or 2-cyanoethyl(dipheriyl)phosphine with M(CO)6 (M=Mo,W) and NaBH4 in refluxing ethanol yielded complexes of the stoichiometry M(CO4)L (L=2(aminomethyl)cyclohexyl(diphenyl) phosphine, 2(aminomethyl)cyclopentyl(diphenyl)phosphine, or 3-aminopropyl (diphenyl) phosphine). The infrared spectra of the complexes display two v(NH) bands at ca. 3360 cm-1 and 3308 cm-1 which are indicative of coordinated NH2 groups which result from the reduction of the CN groups. Four v(CO) bands are observed for the complexes which indicates that the compounds are of cis-configuration.Ball State UniversityMuncie, IN 47306
19

Chiral phosphine synthesis by the application of directed metallation

Lin, Qinghong, Chemistry, Faculty of Science, UNSW January 1999 (has links)
The ortho metallation of some aromatic ring systems has been investigated in regard to the influence of several types of phosphorus-centred directing groups upon the reactivity, regioselectivity, and utility in later synthetic elaboration. The metallation step allows derivatisation in several useful ways, offering several routes to the synthesis of novel chiral ditertiary phosphines. Thus, an ortho lithiation of N,N,N',N'-tetramethyl-P-phenylphosphonic diamide (10) led to the interesting primary phosphine, 2-(diphenylphosphino)phenylphosphine (14), after elaboration of the phosphonic diamide directing group. This primary phosphine undergoes an unprecedented facile phenyl group exchange process between its two phosphorus atoms, upon di-lithiation of the primary phosphorus centre. The primary phosphorus centre of (14) has been elaborated in several ways to yield new ditertiary phosphines. The alkylation of this centre in the copper(I) chelate complex has been investigated in several directions. In another direction, (14) has been chemically elaborated to give a new hybrid chiral ditertiary phosphine ligand, &quotSemiPHOS&quot, containing both a chiral phospholane ring and an adjacent diphenylphosphino group. SemiPHOS has been obtained in optically pure forms by a stereoselective synthesis and, independently, by a resolution procedure on its racemate. The molecular design of SemiPHOS was devised such that, when chelated to a metal atom, a subtle steric interaction appears to allow the chirality of the phospholane ring to influence the neighbouring diphenylphosphino group to adopt a complementary chiral conformation. This idea was tested and evaluated by applying SemiPHOS in catalytic asymmetric hydrogenations of (Z)-a-(Nacylamino) acrylate substrates to produce the R-amino acid precursors. Aryl species lithiated ortho to phosphorus-centred directing groups were coupled oxidatively by a convenient in situ method, to yield biaryl species that could then be elaborated to give biaryl ditertiary phosphine ligands. This method was used to make several atropisomeric chiral ditertiary phosphines.
20

Chiral phosphine synthesis by the application of directed metallation

Lin, Qinghong, Chemistry, Faculty of Science, UNSW January 1999 (has links)
The ortho metallation of some aromatic ring systems has been investigated in regard to the influence of several types of phosphorus-centred directing groups upon the reactivity, regioselectivity, and utility in later synthetic elaboration. The metallation step allows derivatisation in several useful ways, offering several routes to the synthesis of novel chiral ditertiary phosphines. Thus, an ortho lithiation of N,N,N',N'-tetramethyl-P-phenylphosphonic diamide (10) led to the interesting primary phosphine, 2-(diphenylphosphino)phenylphosphine (14), after elaboration of the phosphonic diamide directing group. This primary phosphine undergoes an unprecedented facile phenyl group exchange process between its two phosphorus atoms, upon di-lithiation of the primary phosphorus centre. The primary phosphorus centre of (14) has been elaborated in several ways to yield new ditertiary phosphines. The alkylation of this centre in the copper(I) chelate complex has been investigated in several directions. In another direction, (14) has been chemically elaborated to give a new hybrid chiral ditertiary phosphine ligand, &quotSemiPHOS&quot, containing both a chiral phospholane ring and an adjacent diphenylphosphino group. SemiPHOS has been obtained in optically pure forms by a stereoselective synthesis and, independently, by a resolution procedure on its racemate. The molecular design of SemiPHOS was devised such that, when chelated to a metal atom, a subtle steric interaction appears to allow the chirality of the phospholane ring to influence the neighbouring diphenylphosphino group to adopt a complementary chiral conformation. This idea was tested and evaluated by applying SemiPHOS in catalytic asymmetric hydrogenations of (Z)-a-(Nacylamino) acrylate substrates to produce the R-amino acid precursors. Aryl species lithiated ortho to phosphorus-centred directing groups were coupled oxidatively by a convenient in situ method, to yield biaryl species that could then be elaborated to give biaryl ditertiary phosphine ligands. This method was used to make several atropisomeric chiral ditertiary phosphines.

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