Highly Active Silica Gel‐Supported Metathesis (Pre)Catalysts

Highly active Hoveyda–Grubbs and Hoveyda–Blechert type (pre)catalysts, immobilized on silica gel, are presented. These (pre)catalysts are synthesized in a few steps from readily available precursors and demonstrate high activity in a number of test metathesis reactions. The catalyst is easily separated by simple filtration of the non‐swelling material.