Date of Award

1993

Publication Type

Doctoral Thesis

Degree Name

Ph.D.

Department

Chemistry and Biochemistry

Keywords

Chemistry, Inorganic.

Supervisor

Loeb, Stephen J.,

Rights

info:eu-repo/semantics/openAccess

Abstract

This thesis deals with the design, synthesis and chemistry of four classics potentially binucleatins thioether ligands. Hexadentate macrocycles containing one large central cavity and rigid xylyl groups, as spacing units, comprise the first class of ligand. The coordination chemistry of these ligands with Cu(I), Ag(I) and Pd(II) is presented. The goal of this class of compound is to demonstrate specifically bimetallic coordination to a thioether ligand and subsequent cooperative substrate binding between the centres. The structure of 2,5,8,17,20,23-hexathia- (9.9) -meta-cyclophane, 10, is presented. The second class of compound is comprised of hexadentate thioether molecules which incorporate a central durene fragment as a spacing unit. Thus, the six donor atoms are compartmentalized into two equivalent S3 sites, favouring bimetallic coordination toward the goal of cooperative substrate binding. The synthesis of this class of compound is achieved employing both organic and metal-template methods in order to obtain the desired regioselectivity. The structure of the ligand, 2,5,8,17,20,23-hexathia- (9) (1,2) (9) (4,5)-cyclophane, 19, is presented. This ligand exists in two possible dinucleating coordination modes, depending on the nature of the ancillary ligand, as is demonstrated by the structures of anti- (Cu$\sb2$(PPh$\sb2$Me)$\sb2$(19)) (ClO$\sb4\rbrack\sb2$, anti- (Ag$\sb2$(PPh$\sb3)\sb2$(19)) (BF$\sb4\rbrack\sb2$ and syn- (Cu$\sb2(\mu$-Ph$\rm\sb2PCH\sb2CH\sb2PPh\sb2$)(19)) (PF$\sb6\rbrack\sb2$. Reaction products with Mo(0), Re(I) and Rh(I) are also presented. Attempts to control regioselectivity of the cyclization reaction are discussed and the structure of the product of one of these attempts, 5,20-dioxa-2,8,17,23-tetrathia (9) (1,3) (9) (4,6)-2,5-bis(ethoxy)cyclophane, 35, is presented. Tetradentate acyclic thioether ligands, containing a central durene fragment, comprise the third class of compound. The structure of the ligand, 1,2,4,5-tetrakis-(phenythiomethyl)benzene, 36, is presented. The t-butyl analogue, 37, is also synthesized. These compounds can be selectively either singly cyclopalladated, as shown by the structure of (PdCl(37)), or doubly 1,4-cyclopalladated, as shown by the structures of (Pd$\rm\sb2(CH\sb3CN)\sb2$(37)) (BF$\sb4\rbrack\sb2$, (Pd$\sb2$(pyridine)$\sb2$(36)) (BF$\sb4\rbrack\sb2$ and (Pd$\sb2$(DMF)$\sb2$(36)) (BF$\sb4\rbrack\sb2$. The para-substitution of the dimetallated complexes makes them convenient precursors to linear organometallic coordination polymers and oligomers. Polymers containing pyrazine and 4,4$\sp\prime$-bipyridine are presented. Fluxionality in the $\sp1$H NMR spectra of these complexes is observed and thermodynamic quantities for the inversion process occurring at sulphur are presented. The fourth type of compound synthesized is a heteroditopic macrocycle containing both a thioether and ether chain fused to a common aromatic unit. The thioether moiety of this ligand is shown to complex transition metals (Cu(I), Ag(I), Mo(0), Re(I)) while the crown ether moiety simultaneously complexes an alkali ion (Na$\sp+$, K$\sp+$). This haproselectivity is studied toward the goal of asymmetric substrate interaction with nicotinic acid. The structure of the ligand, 2,5,8-trithia- (9) (1,2)-16,19,22,25,28-pentaoxa- (13) (4,5)cyclophane, 53, is presented.Dept. of Chemistry and Biochemistry. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1993 .S454. Source: Dissertation Abstracts International, Volume: 55-05, Section: B, page: 1843. Adviser: Stephen J. Loeb. Thesis (Ph.D.)--University of Windsor (Canada), 1993.

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