Total Synthesis of Peridinin and Related C37-Norcarotenoid Butenolides
作者:Belén Vaz、Marta Domínguez、Rosana Alvarez、Angel R. de Lera
DOI:10.1002/chem.200600959
日期:2007.1.22
Z-selective Julia reaction and two sequential Stille couplings, the last one producing the isomerisation of the polyene Z double bond. The second route inverts these steps and makes the isolation of the 11'Z stereoisomers as major products possible. An efficient Z to E isomerisation of the final carotenoid skeleton simply uses the Stille reaction conditions at ambient temperature. As the reaction of bromoallene
γ-Allenyl Allyl Benzothiazole Sulfonyl Anions Undergo<i>cis</i>-Selective (Sylvestre) Julia Olefinations
作者:Angel R. de Lera、Belén Vaz、Rosana Alvarez、José A. Souto
DOI:10.1055/s-2004-837214
日期:——
γ-Allenyl allyl benzothiazolyl sulfones 8 and ent-8 provided allenyl trienes and polyenes with cis-selectivities ranging from 71:29 to 100:0 upon condensation (NaHMDS, THF, -78 °C to 25 °C) with a variety of unsaturated aldehydes.