Catálogo de Investigaciones | 2013-2014

FACULTAD 158 Regiocontrolled ring opening of monoprotected 2,3-epoxy-1,4- diols using alkynyl aluminum reagents: synthesis of differentially monoprotected alkynyl triol derivatives The regioselective cleavage of 2,3-epoxyalcohols with alkyl- and alkynylaluminum reagents have become a popular and useful alternative for the construction of polypropionates. In this line, we have developed a second-generation approach and, cis and trans monoprotected 2,3-epoxy-1,4-diols with diethylalkynyl aluminum reagents were studied. Epoxide cleavage reactions of monoprotected TIPS, TBS, PMB and Bn epoxy diols using alane and alanates conditions in toluene or dichloromethane were explored. The alkynyl attack at the C2 epoxide carbon was favored for both, the alane and alanate conditions in toluene, while in dichloromethane the C3 attack was preferred. The best regioselectivities were obtained using the alanates conditions in toluene. This approach provides access to differentiated monoprotected alkynyl triols with high diastereoselectivity. The incorporationof the hydroxymethyl moiety, found in some polyketide systems, was extended to the elaboration of the C12-C17 tedanolide polypropionate chain with the correct relative configuration. dr. raúl r. rodríguez recinto de mayagüez josé a. prieto jaileen rentas universidad de puerto rico 2,3-epoxy-1,4-diols alkynyl aluminum reagents alkynyl triol derivates