The University of Southampton
University of Southampton Institutional Repository

Stereochemically non-rigid transition metal complexes of 2,6-bis(phenyliminomethyl)pyridine and derivatives. Crystal structure of fac- ReBr(CO)(3)(PMTFA) (PMTFA=2,6-pyridylene-bis-(methylene-2-trifluoromethylaniline)

Stereochemically non-rigid transition metal complexes of 2,6-bis(phenyliminomethyl)pyridine and derivatives. Crystal structure of fac- ReBr(CO)(3)(PMTFA) (PMTFA=2,6-pyridylene-bis-(methylene-2-trifluoromethylaniline)
Stereochemically non-rigid transition metal complexes of 2,6-bis(phenyliminomethyl)pyridine and derivatives. Crystal structure of fac- ReBr(CO)(3)(PMTFA) (PMTFA=2,6-pyridylene-bis-(methylene-2-trifluoromethylaniline)
The Schiff bases 2,6-bis(phenyliminomethyl)pyridine and its derivatives (L) form bidentate chelate complexes with transition metals Re-I, Pt-IV and Pd-II of general formulation fac-[ReBr(Co)(3)L], fac-[PtXMe3L] (X = Cl, Br or I), and cis-[Pd(p-CF3C6F4)(2)L]. In solution these complexes are stereochemically non-rigid, undergoing 1,4-metallotropic shifts and restricted rotations of the substituted aromatic rings attached to the metal-coordinated imino nitrogen. Rates and activation energies of these internal motions were measured by one-dimensional NMR bandshape analysis and two-dimensional EXSY NMR experiments over a range of solution temperatures. Free energy values, DeltaG(double dagger) (298.15 K), for the fluxional shifts were in the range 76-97 kJ mol(-1) with the Pd-II complexes having the lowest energies. An X-ray crystal structure of fac-[ReBr(CO)(3)PMTFA] (PMTFA = 2,6-pyridylene-bis(methylene-2-trifluoroaniline)) showed the pendant imine function to be in an E-conformation with its nitrogen trans to the pyridyl nitrogen.
palladium(ii), platinum(iv), rhenium(i), fluxionality, dynamic nmr 2, 6-bispyridine bip, nmr, ligands, x=cl, br
0022-328X
125-134
Creber, M. L.
71d2ca9d-7d07-4571-a634-7afcb7c1ac0c
Orrell, K. G.
e291cfb7-374a-4a7f-8e30-d9513f5203c4
Osborne, A. G.
9430fd91-c186-4b98-a713-74d9b6fbba4b
Sik, V.
ce381a83-89b1-4d4c-82b0-57a0c143dd36
Bingham, A. L.
f9f717a5-bc9c-49da-8358-0b19631e28fd
Hursthouse, M. B.
57a2ddf9-b1b3-4f38-bfe9-ef2f526388da
Creber, M. L.
71d2ca9d-7d07-4571-a634-7afcb7c1ac0c
Orrell, K. G.
e291cfb7-374a-4a7f-8e30-d9513f5203c4
Osborne, A. G.
9430fd91-c186-4b98-a713-74d9b6fbba4b
Sik, V.
ce381a83-89b1-4d4c-82b0-57a0c143dd36
Bingham, A. L.
f9f717a5-bc9c-49da-8358-0b19631e28fd
Hursthouse, M. B.
57a2ddf9-b1b3-4f38-bfe9-ef2f526388da

Creber, M. L., Orrell, K. G., Osborne, A. G., Sik, V., Bingham, A. L. and Hursthouse, M. B. (2001) Stereochemically non-rigid transition metal complexes of 2,6-bis(phenyliminomethyl)pyridine and derivatives. Crystal structure of fac- ReBr(CO)(3)(PMTFA) (PMTFA=2,6-pyridylene-bis-(methylene-2-trifluoromethylaniline). Journal of Organometallic Chemistry, 631 (1-2), 125-134. (doi:10.1016/S0022-328X(01)01050-6).

Record type: Article

Abstract

The Schiff bases 2,6-bis(phenyliminomethyl)pyridine and its derivatives (L) form bidentate chelate complexes with transition metals Re-I, Pt-IV and Pd-II of general formulation fac-[ReBr(Co)(3)L], fac-[PtXMe3L] (X = Cl, Br or I), and cis-[Pd(p-CF3C6F4)(2)L]. In solution these complexes are stereochemically non-rigid, undergoing 1,4-metallotropic shifts and restricted rotations of the substituted aromatic rings attached to the metal-coordinated imino nitrogen. Rates and activation energies of these internal motions were measured by one-dimensional NMR bandshape analysis and two-dimensional EXSY NMR experiments over a range of solution temperatures. Free energy values, DeltaG(double dagger) (298.15 K), for the fluxional shifts were in the range 76-97 kJ mol(-1) with the Pd-II complexes having the lowest energies. An X-ray crystal structure of fac-[ReBr(CO)(3)PMTFA] (PMTFA = 2,6-pyridylene-bis(methylene-2-trifluoroaniline)) showed the pendant imine function to be in an E-conformation with its nitrogen trans to the pyridyl nitrogen.

This record has no associated files available for download.

More information

Published date: 10 August 2001
Keywords: palladium(ii), platinum(iv), rhenium(i), fluxionality, dynamic nmr 2, 6-bispyridine bip, nmr, ligands, x=cl, br

Identifiers

Local EPrints ID: 19461
URI: http://eprints.soton.ac.uk/id/eprint/19461
ISSN: 0022-328X
PURE UUID: 12a85e30-0621-4fa2-b7ea-871cca0747df

Catalogue record

Date deposited: 13 Feb 2006
Last modified: 15 Mar 2024 06:16

Export record

Altmetrics

Contributors

Author: M. L. Creber
Author: K. G. Orrell
Author: A. G. Osborne
Author: V. Sik
Author: A. L. Bingham

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×