Divergent Coordination Mode of Magnesium and Zinc Alkyls Supported by the Multidentate Pyrrolylaldiminato Ligands
|Izabela Kraszewska , Maciej Dranka , Janusz Lewiński|
Warsaw University of Technology, Faculty of Chemistry, Noakowskiego 3, Warszawa 00-664, Poland
Organomagnesium compounds have many application in both organic and organometallic chemistry. Over recent years the exploitation of magnesium and zinc complexes supported by β-diketiminato,  and tropoiminato  ligand systems has provided a number of spectacular results.
As part of ongoing structure and reactivity studies involving the RZn(X,Y) chelate complexes, we have initiated to examine the solid state and solution structure of alkylzinc and magnesium N,N’-chelate complexes based on pyrrolyl ligands. We turned our attention to the bi- and trifunctional pyrrolyladiminato ligands, anticipating that a combination of pyrrole and Schiff base type ligands may provide spectacular results. Additionally, the choice of our target complexes was dictated by the fact that the chemistry of main group metal complexes with bi- and tridentate pyrrolyladiminato ligands remains relatively poorly explored.
Series of zinc and magnesium alkyl complexes supported by pyrrolylaldiminate ligands have been synthesized and structurally characterized. Our studies demonstrate that pyrrolylaldimines are electronically very flexible ligand system. We have found that pyrrolylaldiminate type ligand in magnesium complexes may acts only as σ-N donor ligand, whereas in zinc complexes may acts both: as σ-N donor ligand or the dihapto η2-π-donor by the 2,3-carbon atoms of the pyrrolyl ring.
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Presentation: poster at 18th Conference on Physical Organic Chemistry, Posters, by Izabela Kraszewska
See On-line Journal of 18th Conference on Physical Organic Chemistry
Submitted: 2006-07-11 14:16 Revised: 2009-06-07 00:44