In the presence of a mesoporous aluminosilicate Al-MCM-41, aldolreaction of various silyl enol ethers with both aromatic and aliphatic aldehydes proceeded under mild reaction conditions to afford the corresponding O-silylated aldol adducts in high yields. The solid acid catalyst was easily recovered and reusable three times.
Diiodosamarium an excellent catalyst precursor for Aldolisation and Michael reactions.
作者:Pierre Van de Weghe、Jacqueline Collin
DOI:10.1016/s0040-4039(00)79253-7
日期:1993.6
SmI2 is the precursor of efficient catalysts for the aldolisationreactions of aldehydes and ketones with enol silanes. α,β-unsaturated ketones give 1,4-addidtions selectively.
Mukaiyama aldol and Michael reactions catalyzed by lanthanide iodides
作者:Nicolas Giuseppone、Pierre Van de Weghe、Mohamed Mellah、Jacqueline Collin
DOI:10.1016/s0040-4020(98)00791-1
日期:1998.10
Samariumdiiodide is an efficient catalyst precursor which allows the formation of condensation products between various carbonylcompounds and ketene silyl acetals or enoxysilanes. With α,β-unsaturated carbonylcompounds, 1,2- or 1,4-additions are observed according to the structure of the substrate. α,β-Unsaturated ketones yield to enoxysilanes by selective Michael additions. Aldol poducts are isolated
Towards peptide isostere libraries: aqueous aldol reactions on hydrophilic solid supports
作者:Anette Graven、Morten Grøtli、Morten Meldal
DOI:10.1039/a909246c
日期:——
Polar polyoxyethylene-polyoxypropylene (POEPOP) resin was derivatised with a 4-hydroxymethyl phenoxy linker and used as a solid support for lanthanide triflate catalysed Mukaiyama type solid phase aldol reactions. The conditions were optimised using resin bound 4-alkoxybenzaldehyde and it was shown that use of an aqueous solvent was crucial. Also, the reactions were performed with an N-terminal peptide aldehyde substrate in very high yields. POEPOP resins prepared with different monomer chain lengths and commercially available PEG-grafted NovaSyn TG resin were compared in the reactions.
A cationic iridium complex [Ir(cod)2]SbF6 was found to be a new and efficient Lewis acid catalyst for Mukaiyama aldol and Mannich reactions. Aldehydes react smoothly with silyl enol ethers to give β-siloxy ketones in the presence of 0.5 mol % of [Ir(cod)2]SbF6. The reaction of N-alkyl arylaldimines with ketene silyl acetals in the presence of 5 mol % [Ir(cod)2]SbF6/P(OPh)3 gave β-amino esters. After