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Preparation of SNS Cobalt(II) Pincer Model Complexes of Liver Alcohol Dehydrogenase
Published on: March 19, 2020
Trigonal bi- and monopyramidal cobalt(II) complexes of a novel guanidine-based tripodal ligand
Cassandra E Searls1, Scott T Kleespies, Matthew L Eppright
1Department of Chemistry, Haverford College, 370 Lancaster Avenue, Haverford, Pennsylvania 19041, United States.
Abstract:
The novel ligand DIG(3)tren has three N',N''-diisopropylguanidinyl (DIG) moieties. We report on the structures of two cobalt complexes that show how an isopropylamino group from each DIG acts as a flap that can either close over the metal or rotate away from the metal to open up a site for auxiliary ligand binding. Two of the -NH(iPr) flaps are open in pink [Co(DIG(3)tren)(OAc)]OAc (1), and each of these flaps provides a hydrogen bond to stabilize acetate binding to trigonal bipyrimidal cobalt. The flaps are closed in blue [Co(DIG(3)tren)][BPh(4)](2) (2), yielding a rare example of a trigonal (mono)pyramidal [ML](2+) ion.
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