Stereoselective Hydrosilylation of Enals and Enones Catalysed by Palladium Nanoparticles
作者:Meryem Benohoud、Sakari Tuokko、Petri M. Pihko
DOI:10.1002/chem.201100655
日期:2011.7.18
A highly versatile and efficient hydrosilylation method by palladium nanoparticle catalysis allows the direct and chemoselective synthesis of 1) enolsilanes of high isomeric purity, 2) saturated aldehydes or ketones, or 3) the corresponding saturated acetals from α,β‐unsaturated aldehydes or ketones. The choice of the product is determined by simply switching the solvent from THF to mixtures of THF/water
Smooth and quantitative deprotection of a wide range of acetals and ketals [Eq. (a); R, R(1)=alkyl, aryl, H] under neutral to mildly basic conditions was achieved with catalytic quantities of cerium ammonium nitrate (CAN). The reaction conditions are compatible with a variety of sensitive functional groups, and aldehydes can be liberated from acetals without being oxidized to the corresponding carboxylic
Deprotection of various kinds of acetals sufficiently occured in the presence of Ti4+-exchanged montmorillonite as a recyclable strong solid acid catalyst.
Cerium(IV) Ammonium Nitrate Catalysed Highly Chemoselective Deprotection of Ketals and THP Ethers in the Presence of Enol Triflates
作者:István E. Markó、Nuno Maulide
DOI:10.1055/s-2005-872257
日期:——
The chemoselective, catalytic deprotection of a variety of ketals, THP, and selected silyl ethers can be efficiently performed, in the presence of enol triflates, by the action of cerium(IV) ammoniumnitrate (CAN).