Ravindran, Mythili (1991) Synthesis and structural studies of N - and O - donor complexes of transition and post-transition metal halides. PhD thesis, University of Warwick.

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Abstract

Trimethylamine reacts with MCl2 (M = Mn, Cd, Cu) to give mono adducts of the type MC12Nme3. Recrystallization of MnC12-Nme3 (1) from the polar solvent acetonitrile yields the anionic complexes [NMe3H] [MnCl3] (II) and [Nme3H]2 [MnCl4Δ] (III) both from the same solution. Similarly CuCl2NMe3 (IV) gives lNMe3H][CdCl3\ (V). Recrystallization of CuCliUMe3 (VI) from the chlorinated solvent CH2CI2 yields the anionic complex [Me3NCH2Cl]2 [CuC1Δ] (VII). Compounds (II). (V) and (VII) were further investigated by X-ray crystal structure determinations.
The co-ordination chemistry of Group VB trichlorides with the neutral O-donor (crown ether) ligands 1,4,7,10-tetraoxacyclododecane (I2-C-4), 1,4,7,10,13-
pentaoxacyclopentadecane (I5-C-5) and 1,4,7,10,13,16-hexaoxacyclooctadecane (18-C- 6) have been investigated. 12-C-4 and 15-C-5 form neutral adducts with the pyramidal MCI3 (M = As, Sb, Bi) where all oxygen atoms of the crown are co-ordinated to the metal atom in a half-sandwich structure.
For I8-C-6, AsC13 does not give complex formation, instead the crown ether forms a bis-adduct (18-C-6).2CH3CN with the solvent acetonitrile. SbC13 forms a half-sandwich adduct with I8-C-6 but with an extra molecule of CH3CN trapped in the lattice and BiC13 forms a 2:1 complex which has the ionic formulation 1B2C12(18-C-6)12 + lB12CI312 Here the bismuth cation is eight co-ordinate involving all six oxygen atoms of the crown and the two chlorine atoms.
The crown ethers give no simple adducts with the pentahalide SbC15. The crystals obtained from the reactions of I2-C-4 and I8-C-6 with SbC15 are the unexpected hydroniumfcrown) hexachloroantimon(V)ate salts, |H3O(12-C-4)2] (SbC1o1) and
[H3O(18-C-6)] [SbC1o) respectively. I5-C-5 gives the neutral Sb(lll) adduct SbC13(l5-C-5) as the major product and the hydroniumfcrown) hexachloroantimon(V)ate salt as the minor product. A plausible mechanism for the formation of hydronium antimon(V)ate salts is presented and discussed.
In the preliminary study of sterically crowded aryloxide complexes of Group VB chlorides, the reaction between SbCli and the extremely bulky 2,6-di(tertiary butyl) phenoxide has been investigated. This leads to the formation of 22' .6,6’ -tetra (tertiary butyl) diphenoquinone (A) via a redox reaction. The crystal structure of this oxidation product has been determined via an X-ray study and a plausible mechanism for the for­mation of (A) is presented and discussed.

Item Type:	Thesis or Dissertation (PhD)
Subjects:	Q Science > QD Chemistry
Library of Congress Subject Headings (LCSH):	Trimethylamine, Halides, Chemistry, Inorganic, Chemistry, Physical and theoretical, Chemistry, Organic, Inorganic compounds -- Synthesis
Official Date:	January 1991
Dates:	Date Event January 1991 Submitted
Institution:	University of Warwick
Theses Department:	Department of Chemistry
Thesis Type:	PhD
Publication Status:	Unpublished
Supervisor(s)/Advisor:	Willey, Gerald
Extent:	i, 196 leaves : illustrations
Language:	eng

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