Synthesis and x-ray structural characterization of binuclear iridium(I) and rhodium(I) hydroxypyridinate complexes. 1. Complete assignment of the /sup 1/H NMR spectra by two-dimensional and NOE techniques. The nature of inside and outside /sup 1/H chemical shift differences

Journal Article · Wed Sep 21 00:00:00 EDT 1988 · Inorg. Chem.; (United States)

DOI:https://doi.org/10.1021/ic00292a017· OSTI ID:6046854

Rodman, G S; Mann, K R

Six new d/sup 8/-d/sup 8/ complexes, (Ir(COD)(..mu..-hp))/sub 2/, (Ir(COD)(..mu..-mhp))/sub 2/, (Ir(COD)(..mu..-chp))/sub 2/, (Ir(COD)(..mu..-2hq))/sub 2/, (Rh(COD)(..mu..-hp))/sub 2/, and (Rh(COD)(..mu..-mhp))/sub 2/ (hp = 2-hydroxyphridinate, mhp = 6-methyl-2-hydroxypyridinate, chp = 6-chloro-2-hydroxypyridinate, 2hq = 2-hydroxyquinolate, COD = 1,5-cyclooctadiene), were synthesized and characterized by /sup 1/H NMR, /sup 13/C NMR, and IR spectroscopy and FAB mass spectrometry. X-ray crystallographic analyses of the isostructural (M(COD)(..mu..-mhp))/sub 2/ (M = Ir and Rh) complexes confirmed the binuclear nature of the complexes. The complete assignment of the /sup 1/H NMR spectrum of (Ir(COD)(..mu..-hp))/sub 2/ (and by analogy, the spectra of the other five complexes) was carried out with selective decoupling, nuclear Overhauser effect (NOE), and two-dimensional NMR techniques. The NOE observed between hp proton H5 and COD proton H15 allowed the precise assignment of all 12 COD resonances. Olefinic proton H12 (trans to N and outside) resonates downfield of olefinic proton H11 (trans to N and inside). Olefininc proton H15 (trans to O and outside) resonates upfield of olefinic proton H16 (trans to O and inside). The endo methylene protons resonate upfield of the exo methylene protons. The inside/outside chemical shift differences observed for these compounds are ascribed to steric and magnetic anisotropy effects. The crystallographic data are presented. The molecular structure of the complexes is discussed in detail. 39 references, 5 figures, 9 tables.

• Research Organization: Univ. of Minnesota, Minneapolis (USA)
• OSTI ID: 6046854
• Journal Information: Inorg. Chem.; (United States), Vol. 27:19
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
HYDROXY COMPOUNDS
SYNTHESIS
IRIDIUM COMPLEXES
PYRIDINES
RHODIUM COMPLEXES
CRYSTAL STRUCTURE
EXPERIMENTAL DATA
MOLECULAR STRUCTURE
AZINES
COMPLEXES
DATA
HETEROCYCLIC COMPOUNDS
INFORMATION
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
TRANSITION ELEMENT COMPLEXES
400201* - Chemical & Physicochemical Properties
400202 - Isotope Effects
Isotope Exchange
& Isotope Separation