Catálogo de Investigaciones | 2013-2014

157 CATÁLOGO DE INVESTIGACIONES | AÑO ACADÉMICO 2013 -2014 Development of a one-step procedure for the synthesis of functionalized allylic alcohols by the cleavage of epoxides with trans - and cis - alkenyl alanates derivatives: application to the construction of polyketide fragments Several methods for the synthesis of polyketide fragments have been developed, but the epoxide cleavage with carbon nucleophiles for such synthesis has become a useful approach. In order to contribute to this area, we have proposed the development of a two-step procedure , which incorporate the hydroalumination-iodination of propargyl alcohols and 2) subsequent preparation of functionalized alkenyl alanates to mediate the ring opening of epoxides. Based on previous reports we postulate that the epoxide cleavage with our alkenyl aluminum ate derivatives with terminal and unhindered epoxides will provide the construction of chiral cis -and trans allylic alcohols. Furthermore, a one-step procedure has been also proposed using propargyl alcohol. This procedure will be based on the carbometalation of terminal alkynes, ate complexation of the alane with n -BuLi, and addition of epoxide. Additionally, we will explore the reactivity of the copper-catalyzed oxygenated alkenyl Grignard intermediate toward the cleavage of various terminal epoxides. These procedures will demonstrate the utility of our new epoxide-cleavage methodology mediated by oxygenated alkenyl alanates and Grignard reagents to the enantio- and regioselective construction of polypropionate and polyols fragments in few steps. This will expand the applicability of our methodology for the synthesis of polyketide natural products and present potential opportunities for increase or modified biological and therapeutic activity. dr. raúl r. rodríguez verónica acosta ponce de león y robby l. martínez vázquez recinto de mayagüez development epoxides trans and cis alkenyl alanates derivatives