Investigations of Racemic and Quasiracemic Metal Complexes of Substituted Benzoylalanines with Nickel, Cobalt, and Zinc
Presentation Type
Poster
Faculty Advisor
Mark Whitener
Access Type
Event
Start Date
26-4-2023 12:30 PM
End Date
26-4-2023 1:30 PM
Description
Two molecules of opposite handedness that are chemically distinct which cocrystallize together produce a quasiracemate. Many quasiracemates consist of a molecule with R configuration at a chiral center with one functional group paired with a second molecule with an S configuration with a different functional group. These two molecules usually assemble about a pseudo center of symmetry. This approximately centrosymmetric relationship in the quasiracemate often mimics the arrangement of the two enantiomers in the true racemates of either of the two components. These compounds are studied to examine how the slight change in chemical makeup of a molecule could change the crystal packing, and potentially be used to design a crystal with desired properties. Most work on quasiracemates have used organic molecules. One class of quasiracemates exploits the strong tendency of carboxylic acids to form inversion related cyclic dimers. In a similar fashion, square planar metal complexes assemble a centrosymmetric-like arrangement of ligands with the metal serving as the inversion center. Previously, complexes of square planar copper (II) were explored to prepare racemic/quasiracemate-like complexes. The current work builds upon those results and extends the research to complexes which have cobalt (II), nickel (II), and zinc (II) centers. Our chiral ligands of choice are substituted benzoylalanines. We attempted to prepare quasiracemic crystals for each transition metal while changing multiple variables such as solvent, nitrogen ligands (imidazole and pyridine), and crystallization methods. Latest results will be reported
Investigations of Racemic and Quasiracemic Metal Complexes of Substituted Benzoylalanines with Nickel, Cobalt, and Zinc
Two molecules of opposite handedness that are chemically distinct which cocrystallize together produce a quasiracemate. Many quasiracemates consist of a molecule with R configuration at a chiral center with one functional group paired with a second molecule with an S configuration with a different functional group. These two molecules usually assemble about a pseudo center of symmetry. This approximately centrosymmetric relationship in the quasiracemate often mimics the arrangement of the two enantiomers in the true racemates of either of the two components. These compounds are studied to examine how the slight change in chemical makeup of a molecule could change the crystal packing, and potentially be used to design a crystal with desired properties. Most work on quasiracemates have used organic molecules. One class of quasiracemates exploits the strong tendency of carboxylic acids to form inversion related cyclic dimers. In a similar fashion, square planar metal complexes assemble a centrosymmetric-like arrangement of ligands with the metal serving as the inversion center. Previously, complexes of square planar copper (II) were explored to prepare racemic/quasiracemate-like complexes. The current work builds upon those results and extends the research to complexes which have cobalt (II), nickel (II), and zinc (II) centers. Our chiral ligands of choice are substituted benzoylalanines. We attempted to prepare quasiracemic crystals for each transition metal while changing multiple variables such as solvent, nitrogen ligands (imidazole and pyridine), and crystallization methods. Latest results will be reported