TITLE:
SnIV and ZrIV Compounds of a C3-Symmetric Ligand with Amine [ONN] and [ONNO] Coordination Sites
AUTHORS:
Carolina von Eßen, Iris M. Oppel
KEYWORDS:
Reduction, Triaminoguanidinium, [ONN]/[ONNO] Binding Pockets, SnIV Complex, ZrIV Complex
JOURNAL NAME:
International Journal of Organic Chemistry,
Vol.7 No.4,
November
24,
2017
ABSTRACT: This
contribution describes the synthesis and structural characterization of a triaminoguanidinium (TAG)-based ligand [H6(OMe)3Limin]BF4 (1) containing imine bonds (Limin)
and its reduction with a dimethylamino borane complex to the corresponding
amine compound (Lamin)[H9(OMe)3Lamin]OTs (2). In solution, both ligands are C3-symmetric but crystal
structures show the great influence of the reduction on the molecular structure.
We show that the planar imine ligand is converted to a highly flexible compound
which has nine potential coordination sites, three
phenoxy and six amine donors, for binding metal ions. First solid state
structures of 1:1 (metal:ligand) coordination compounds with SnIV and ZrIV are presented. SnIV exhibits an octahedral
coordination sphere and is bound in a facial [ONN] coordination pocket. ZrIV is pentagonal bipyramidal coordinated and the ligand stabilizes this with its’
[ONNO] binding sites.