Saul Winstein proved anchimeric assistance is stereoselective in forming these compounds, leading to his debate with Herb Brown about 2-norbornene.
RM Coates names an unusual polycyclic example of these compounds derived from pentacyclononane. Multiple reactions that form the same one of these compounds show memory effects. These compounds have a delta-sub-sigma value in carbon NMR of up to 400 ppm. Saul Winstein proved anchimeric assistance is stereoselective in forming these compounds, leading to his debate with Herb Brown about 2-norbornene. Though not boranes, (*) nonclassical depictions of these compounds give them bridged three-center two-electron bonds. George Olah showed that stable media for these compounds includes antimony pentafluoride. These compounds, which undergo spontaneous methanide migrations, are formed as intermediates in isobutylene polymerization, in Friedel-Crafts alkylation, and in SN1 reactions. For 10 points, name these intermediates in which carbon has a positive charge.
RM Coates names an unusual polycyclic example of these compounds derived from pentacyclononane.
carbocations [or carbonium ions; or carbenium ions; prompt on ions or cations]