Stephen A. Godleski
Our Groupís research interests are currently focused in two main areas: the use of organosilver intermediates as precursors to synthetically useful radicals and the rearrangement of vinyl epoxides to dihydrofurans with tin catalysts in ionic liquids. Organic radicals can be generated from a variety of precursors and subsequently employed in cyclization reactions. Radical mediated cyclizations can be advantaged relative to ionic processes due to their chemoselectivity, better tolerance for steric crowding and mild reaction conditions. Organosilver intermediates have a strong propensity to undergo homolytic cleavage even when the radical produced is highly unstable. Our research utilizes this property to generate unstable radicals and then investigate the scope and limitations of their cyclization reactions. Organotin iodides can be employed in ionic liquid- quat salt solutions as very efficient catalysts for the rearrangement of vinyl epoxides to the corresponding dihydrofuran. Our research in this area studies the use of this reaction in bicyclic epoxide systems as well as the stereochemical aspects of this rearrangement.
Stephen N. Falling, John R. Monnier, Gerald W. Phillips, Jeffrey S. Kanel, and Stephen A. Godleski, "Development of an Industrial Process for the Lewis Acid/Iodide Salt-Catalyzed Rearrangement of 3,4-Epoxy-1-Butene to 2,5-Dihydrofuran", Catalysis of Organic Reactions, Vol. 115, (2006)
"Continuous Process for the Manufacture of 2,5-Dihydrofuran from Epoxybutenes", US 5,315,019 1994.
"Isomerization of Epoxyalkenes to 2,5-Dihydrofurans and Catalyst Compositions Useful Therefore", US 5,082,956 1992.