title: Interaction of In(I) and Tl(I) cations with 2,6-diaryl pyridine ligands: cation encapsulation within a very weakly interacting N/arene host environment.
abstract: The interaction of 2,6-dimesitylpyridine with Tl(I) and In(I) cations has been investigated with a view to developing tractable molecular M(I) compounds which are soluble in organic media. In stark contrast to isosteric and isoelectronic terphenyl systems, complexes featuring the [(2,6-Mes(2)py)M](+) fragment feature very weak metal-ligand interactions in the solid state, as revealed by M-N distances of the order of 2.45 Å (M = In) and 2.64 Å (M = Tl). While additional weak π interactions are observed with arene solvate molecules in these systems, the related 2:1 complex [(2,6-Mes(2)py)(2)In][BAr(f)(4)] features an In(I) center wholly encapsulated by the bulky Mes(2)py donors, and even longer In-N distances [2.586(6) and 2.662(5) Å]. These contacts are about 0.5 Å greater than the sum of the respective covalent radii (2.13 Å) and provide evidence for an effectively "naked" In(I) cation stabilized to a minor extent by orbital interactions.
authors.affiliation: Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, UK OX1 3QR.
authors.forename: Hassanatu B
authors.initials: HB
authors.lastname: Mansaray
authors.forename: Christina Y
authors.initials: CY
authors.lastname: Tang
authors.forename: Dragoslav
authors.initials: D
authors.lastname: Vidovic
authors.forename: Amber L
authors.initials: AL
authors.lastname: Thompson
authors.forename: Simon
authors.initials: S
authors.lastname: Aldridge
mesh_terms: D002412:Cations / Q000737:chemistry; D018360:Crystallography, X-Ray; D007204:Indium / Q000737:chemistry*; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D011725:Pyridines / Q000737:chemistry*; D013793:Thallium / Q000737:chemistry*
chemical_list: D002412:Cations; D008024:Ligands; D009942:Organometallic Compounds; D011725:Pyridines; D007204:Indium; D013793:Thallium; C023666:pyridine