Jump to main content
Jump to site search

Issue 2, 2010
Previous Article Next Article

Tautomerisation and hydrogen-bonding interactions in four-coordinate metal halide and azide complexes of N-donor-extended dipyrromethanes

Author affiliations

Abstract

The synthesis and structures of Fe, Co, and Zn halide complexes [MX2(H2L)] (M = Fe, X = Br; M = Co, Zn, X = Cl) of the N-donor extended dipyrromethane ligand H2L are described, from which it is clear that bond rearrangements from imine-pyrrole to amine-azafulvene tautomers occur on metal co-ordination, both in the solid state and in solution. In the structure of [FeBr2(H2L)], this H-migration results in a pendant amine that is involved in both inter- and intramolecular hydrogen bonds to the bromide ligands, so forming a dimer. As the tautomerisation renders the N–H protons less acidic, metal-based ligand substitution reactions can occur in favour of deprotonation. As such, the reaction between [MCl2(H2L)] (M = Co, Zn) and NaN3 results in the formation of the bis(azide) complexes [M(N3)2(H2L)] which for Co displays both inter- and intramolecular N–H⋯N3–Co hydrogen bonds in the solid state. In contrast, reactions of the dihalides with the lithium bases LiNMe2 or LiMe (M = Fe), or reduction reactions with C8K (M = Fe, Co) result in the formation of the known dinuclear helicates [M2(L)2].

Graphical abstract: Tautomerisation and hydrogen-bonding interactions in four-coordinate metal halide and azide complexes of N-donor-extended dipyrromethanes

Back to tab navigation

Supplementary files

Additions and corrections

Publication details

The article was received on 19 May 2009, accepted on 31 Jul 2009 and first published on 24 Aug 2009


Article type: Paper
DOI: 10.1039/B909842A
Citation: Dalton Trans., 2010,39, 418-425
  •   Request permissions

    Tautomerisation and hydrogen-bonding interactions in four-coordinate metal halide and azide complexes of N-donor-extended dipyrromethanes

    S. D. Reid, C. Wilson, A. J. Blake and J. B. Love, Dalton Trans., 2010, 39, 418
    DOI: 10.1039/B909842A

Search articles by author

Spotlight

Advertisements