Ligand effects on the stereochemistry of Stille couplings, as manifested in reactions of Z-alkenyl halides
作者:Guo-ping Lu、Karl R. Voigtritter、Chun Cai、Bruce H. Lipshutz
DOI:10.1039/c2cc33294a
日期:——
Unexpected losses in stereochemistry from Stille reactions involving Z-alkenyl halides have been shown to be ligand dependent. A new set of reaction conditions has been developed that, in most cases, leads to highly stereoselective cross-couplings under mild conditions, along with improved yields.
Intramolecular Diels–Alder Reactions of Cycloalkenones: Translation of High<i>Endo</i>Selectivity to<i>Trans</i>Junctions
作者:Audrey G. Ross、Xiaohua Li、Samuel J. Danishefsky
DOI:10.1021/ja307708q
日期:2012.9.26
Intramolecular Diels-Alderreactions of cyclobutenone and larger cycloalkenones are described. High levels of endo addition attained from Lewis acid catalysis translate to trans hydrindene junctions upon fragmentation of the tricyclic adducts.