Jochanan Blum, Zackaria Nairoukh, and David Avnir. 2015. “Better Catalysis with Organically Modified Sol-gel Materials.” In The Sol-Gel Handbook, 2: Pp. 963–986. Wiley-VCH. Publisher's Version Abstract
Sol–gel materials have a number of properties that make them ideal for supporting heterogeneous catalysis. This chapter focuses on the use of organic molecules to affect the catalytic properties of sol-gel materials (e.g., tailoring-specific porosity); on the use of organically modified precursors; on the entrapment of organometallic catalysts; and briefly on the entrapment of enzymes and catalytic antibodies. All of these utilize the special property of sol-gel materials, namely, that they are prepared at convenient temperatures. The chapter brings an example of how the stereochemistry of a catalytic reaction was controlled by sol-gel imprinting with the desired stereoisomer. It mentions the enantioselective reduction of itaconic acid by a number of entrapped chiral organometallic catalysts. The chapter also discusses industrial success stories of sol–gel-based catalysis.
Abstract The regio- and stereoselective formation of stereodefined polysubstituted silyl ketene aminals is easily achieved through selective combined carbometalation?oxidation?silylation reactions. These substrates are ideal candidates for Mukaiyama aldol reactions with aliphatic aldehydes as they give the aldol products with a quaternary carbon stereocenter α to the carbonyl groups in outstanding diastereoselectivities.