Investigations of Intramolecular Copper (I)-arene Interactions using a NS2-macrocyclic Ligand with Different Pendant Aryl Arms
Date of Award
Honors Thesis (Open Access)
Colby College. Chemistry Dept.
Rebecca R. Conry
Two macrocyclic ligands with a pendant phenyl group -N-[2-(l-phenyl)ethyl]-1-aza-4,8di thiacyclodecane (L1) and N-[2-0-phenyl)propyl]-1-aza-4,8-dithiacyclodecane, (L2) has been synthesized and characterized. The copper(I)-triphenylphosphine complex [LICu(PPhJ)]OTf , (2) was synthesized from L1 1/2(C6H6)[CuOTf]2, and PPh3. The complexes [LICu]OTf 1 and [L2Cu]OTf 3 were also synthesized and characterized using DC and IH NMR, UV-vis and lR spectroscopy, and ESI-MS. In CD2Cl2, 1 was found to have a fluxional behavior with the barrier ΔG to the process estimated at 9-11 kcal/mol. Variable temp. NMR spectroscopy of 1 gave compelling evidence that the phenylappended group is bound in an intramolecullar η2-fashion with the copper center. At room temperature, 1 and 3 were found to be in a fluxional process of the bound and unbound arene system. In CD2CI2 the barrier to the fluxional process for 2 was found to be much less than 1; ΔG = 2-8 keal/mol. The location of binding on the aryl linker arm for 1 and 3 is hypothesized to be at the π-system adjacent to the linker arm. (DFT) pBP/DN• and RHF -6-31 g* molecular orbital calculations have been performed to better understand the complexes 1 and 3.
Cooperative binding, Ligand binding, Aromatic compounds, Copper, arene interactions, NS2-macrocyclic ligand, pendant aryl arms
Recommended CitationLee, Paul J., "Investigations of Intramolecular Copper (I)-arene Interactions using a NS2-macrocyclic Ligand with Different Pendant Aryl Arms" (2002). Honors Theses. Paper 255.
Colby College theses are protected by copyright. They may be viewed or downloaded from this site for the purposes of research and scholarship. Reproduction or distribution for commercial purposes is prohibited without written permission of the author.