1,3-Addition of silyl enol ethers to nitrones catalyzed by mesoporous aluminosilicate

Mesoporous aluminosilicate (Al-MCM-41) was found to be an effective and reusable catalyst for 1,3-addition of silyl enol ethers to nitrones. The reaction proceeded under mild reaction conditions to afford the corresponding β-(siloxyamino)ketones in high yields. Furthermore, a unique chemoselectivity of a nitrone over an aldehyde and an acetal, which are more reactive toward silyl enol ether in the presence of Al-MCM-41 than a nitrone, was observed.