Heterogeneous Stille and Sonogashira cross-coupling reactions over palladium anchored mesoporous silica catalyst

A Pd-based heterogeneous catalyst (Pd(II)-MCM-41) derived from post-synthesis modification of mesoporous silica, MCM-41, has been successfully employed in catalytic Stille and Sonogashira cross-coupling reactions. The catalyst affords good yields in all cross-coupling reactions. Notably, the catalyst is capable of activating less reactive chlorobenzene with moderate yield in both the coupling reactions. The reactions take place smoothly in air without any activating ligand. It is observed that in the case of Stille reactions, the less expensive organotin reagent, Ph3SnCl, can be used instead of the conventional expensive reagent, Bu3SnPh. Both the organotin reagents exhibit comparable reactivity in Stille reactions catalyzed by Pd(II)-MCM-41. The catalyst is easily recoverable and reusable at least three times without significant loss of catalytic activity.