Pushing the Boundaries of Vinylogous Reactivity: Catalytic Enantioselective Mukaiyama Aldol Reactions of Highly Unsaturated 2‐Silyloxyindoles
抄録
<jats:title>Abstract</jats:title><jats:p>The first example of catalytic, enantioselective hypervinylogous Mukaiyama aldol reaction (HVMAR) involving multiply unsaturated 2‐silyloxyindoles is reported. The reaction utilizes a chiral Lewis base‐catalyzed Lewis acid‐mediated technology to deliver homoallylic 3‐polyenylidene 2‐oxindoles with extraordinary levels of regio‐, enantio‐, and geometrical selectivity. This work highlights a subtle yet decisive influence of the indole <jats:italic>N</jats:italic>‐substituents on the propagation of the vinylogous reactivity space of the donor substrates up to ten bonds away from the origin of the vinylogy effect. Analysis of the <jats:sup>13</jats:sup>C NMR chemical shifts of the C‐ω remote site within homologous silyloxyindole donors enabled rationalization of the results and easy qualitative prediction of the HVMAR reactivity/inertia toward a given aldehyde acceptor.</jats:p>
収録刊行物
-
- Chemistry – A European Journal
-
Chemistry – A European Journal 21 (17), 6433-6442, 2015-03-03
Wiley