23721-98-4Relevant articles and documents
Complexes of Functionalised Phosphine Ligands. Part 1. Complexes of Fe(III), Co(III), Ni(II) and Re(V) with Tridentate Schiff Bases having PNO, NNO and NNS Donor Sets. Crystal Structures of 2-(Ph2PC6H4N=CH)C6H4OH and 2>
Dilworth, Jonathan R.,Howe, Stuart D.,Hutson, Antony J.,Miller, John R.,Silver, Jack,et al.
, p. 3553 - 3562 (2007/10/02)
The Schiff bases 2-C6H4OH (n = 3, HL1 or 2 HL2), 2-(RCH=N)C6H3(OH)X-4 (R = 2-Ph2PC6H4, X = H HL3; R = 2-C5H4N, X = H HL4; R = 2-C5H4N, X = Cl HL5) were synthesised from the appropriate amine and aldehyde.On deprotonation these all functioned as tridentate monoanionic ligands to give complexes (1+) and (1+) with Fe(III) and Co(III) and neutral complexes of stoichiometry NiL2 with Ni(II).The iron complexes were examined by Moessbauer spectroscopy which indicated the presence of two iron sites in 12>(1+) with a spin-state equilibrium dependent on both temperature and the counter ion.The complex 32>(1+) showed a single iron site, again with a spin state dependent on counter ion and temperature.The crystal structures of HL3 and 32>(1+) have been determined.The distortions in free HL3 predispose it for co-ordination in a fac geometry to the Co with cis-PPh2 groups, and the changes occurring on co-ordination are discussed in detail.Reaction of RCHO (R = 2-Ph2PC6H4 or 2-C5H4N) with 2-aminobenzenethiol gave stable thiazoles which did not ring open to give tridentate ligands even on reaction with base and/or metal ions.
