DMAP-Mesoporous Silica Nanosphere as a Heterogeneous Nucleophilic Catalyst

Significance

4-(Dialkylamino)pyridine-functionalized mesoporous silica nanosphere (DMAP-MSN) was synthesized and used as a heterogeneous catalyst for the Baylis-Hillman reaction. Thus, the reaction of 4-nitrobenzaldehyde (1) with methyl vinyl ketone (2) was carried out in the presence of catalytic amounts of DMAP-MSN (30 mol%) in THF-H₂O (3:1) at 50 °C for 24 h to give the corresponding Baylis-Hillman product 3 in 99% yield. In contrast to the homogeneous DMAP-catalyzed Baylis-Hillman reaction, undesired diadduct and Michael adduct were not observed under the present conditions. DMAP-MSN was used also for acylation and silylation of alcohols where high recyclability and stability of DMAP-MSN were demonstrated.