Friedel dual catalysis

Scheme 43.16 Friedel-Crafts alkylation of indoles with simple a,P-unsaturated ketones by dual catalysis.

Olefins are formed by dehydrogenation of the n-paraffin feed over the metallic hydrogenation-dehydrogenation function and are adsorbed on the acidic surface of the catalyst as carbonium ions by proton addition. After skeletal isomerization they are desorbed as isoolefins and subsequently hydrogenated to the corresponding isoparaffins. The net result (i.e., the formation of carbonium ions) of the action of metal and acid in dual function catalysis is, on pure Friedel-Crafts type catalysts, described by the scheme ... 

Most recently, a dual catalytic Friedel-Crafts reaction that merges organocatalysis and transition metal catalysis for the asymmetric synthesis of annulated pyrroles has been achieved. 

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