Synthesis of functionalized carbo- and heterocycles via gold-catalyzed cycloisomerization reactions of enynes
作者:Lucie Leseurre、Chung-Meng Chao、Tomohiro Seki、Emilie Genin、Patrick Y. Toullec、Jean-Pierre Genêt、Véronique Michelet
DOI:10.1016/j.tet.2008.11.105
日期:2009.2
conditions were compatible with various functional groups on the nucleophiles. Severe limitations were observed when the allylic position of the enyne is substituted by electron-withdrawing groups. The mechanism of the reaction was investigated via the synthesis of a deuterated aromatic ring: we showed that the source of proton involved in the protodemetallation step originates from the acidic activated
Asymmetric Au-catalyzed domino cyclization/nucleophile addition reactions of enynes in the presence of water, methanol and electron-rich aromatic derivatives
作者:Alexandre Pradal、Chung-Meng Chao、Maxime R. Vitale、Patrick Y. Toullec、Véronique Michelet
DOI:10.1016/j.tet.2011.03.071
日期:2011.6
system is described for the asymmetric domino cyclization/functionalization reactions of functionalized 1,6-enynes in the presence of an external nucleophile. The use of (R)-4-MeO-3,5-(t-Bu)2-MeOBIHEP ligand associated with gold led to clean rearrangements implying the formal addition of an oxygen or carbon nucleophile to an alkene followed by a cyclization process. The enantiomeric excesses were highly
作者:Chung-Meng Chao、Maxime R. Vitale、Patrick Y. Toullec、Jean-Pierre Genêt、Véronique Michelet
DOI:10.1002/chem.200802341
日期:2009.1.26
Gold efficiency: An efficient AuI catalytic system is described for the enantioselective hydroarylation/cyclization reaction of 1,6‐enynes (see scheme). Use of the (R)‐4‐MeO‐3,5‐(tBu)2‐MeOBIPHEP–gold complex led to clean rearrangements implying the formal addition of a carbon nucleophile (1,3,5‐trimethoxybenzene, 1,3‐dimethoxybenzene, pyrrole, 1,3,5‐trimethoxy‐2‐bromobenzene and indole derivatives)
The platinum(II) chloride/silver hexafluoroantimonate (PtCl2/AgSbF6) catalytic system associated with atropisomeric ligand Ph-BINEPINE promotes a stereoselective tandem hydroarylation (Friedel–Crafts-type addition) of electron-rich aromatic and heteroaromatic derivatives to unactivated alkenes followed by a CC bond cyclization reaction (ee up to 96%). Some evidence shows that the catalytic species