Structure and Dynamic Behavior of Selected Organolithium    Compounds
{'Code': '03090003', 'Directorate': {'LongName': 'Direct For Mathematical & Physical Scien'}, 'Division': {'LongName': 'Division Of Chemistry'}}
{'SignBlockName': 'Paul W. Jennings'}
This project in the Organic Dynamics Program by Professor                       Gideon Fraenkel of the Ohio State University is aimed at the                    elucidation of the structure of organolithium compounds by                      Nuclear Magnetic Resonance Spectroscopy.  In addition, the Ohio                 State group will investigate the way that organolithium                         compounds group together in solution (aggregation).  This work                  is highly significant in that organolithiums are widely used by                 organic chemists as intermediates in the synthesis of new and                   important compounds.                                                                                                                                            A variety of NMR techniques including line-shape analysis and                   NOE experiments will be applied to the study of structure and                   dynamic behavior of model solvated organolithium compounds                      enriched in Li-6, and if necessary C-13 at the alpha carbon,                    selected to reveal specific effects and interactions.  Use of                   very low temperature, down to 120 degrees K, and low                            concentrations to ensure that C-Li bond exchange processes do                   not perturb the spectra, will allow observation of specific                     structural features.  These include a) possible interactions of                 (RLi)n species with isolated double bonds; b) nature of ligand                  solvation and accompanying thermodynamics; c) the degree of                     non-planarity of allyllithiums; and d) structure of                             theoretically interesting dilithium compounds.  Cisoid diamines                 and triamines, some chiral, will be synthesized to see if they                  stabilize different (RLi)n aggregates, and also to ensure slow                  lithium ligand exchange.                                                                                                                                        The architecture of ion pairs will be studied via NOE                           experiments including ion pairs in liquid crystal media making                  use of the structural dependence of the dipolar couplings.                      Exchange averaging in the latter spectra will allow measurement                 of very fast rates of exchange of ion among ion pairs.                                                                                                          The signal averaging of C-13/Li-6 couplings and shifts among                    species seen in NMR data for RLi compounds will be analyzed to                  determine exchange rates, and via kinetics and structural                       information, to learn about exchange mechanisms at equilibrium.
{'FirstName': 'Gideon', 'LastName': 'Fraenkel', 'EmailAddress': 'Fraenkel@mps.ohio-state.edu', 'StartDate': '01/01/1989', 'EndDate': None, 'RoleCode': 'Principal Investigator'}
{'Name': 'Ohio State University Research Foundation -DO NOT USE', 'CityName': 'Columbus', 'ZipCode': '432101016', 'PhoneNumber': '6146888734', 'StreetAddress': '1960 KENNY RD', 'CountryName': 'United States', 'StateName': 'Ohio', 'StateCode': 'OH'}
{'Code': '1944', 'Text': 'BIMOLECULAR PROCESSES'}
{'url': 'https://www.nsf.gov/awardsearch/download?DownloadFileName=1988&All=true', 'xml': '8817746.xml'}