Asymmetric organocatalytic conjugate addition of malonates to enones using a proline tetrazole catalyst
作者:Kristian Rahbek Knudsen、Claire E. T. Mitchell、Steven V. Ley
DOI:10.1039/b514636d
日期:——
5-Pyrrolidin-2-yltetrazole performs as a useful organocatalyst for the asymmetric addition of malonates to a range of enones, with good to excellent enantioselectivities.
Stereoselective Synthesis of Cyclohexanes via an Iridium Catalyzed (5 + 1) Annulation Strategy
作者:Wasim M. Akhtar、Roly J. Armstrong、James R. Frost、Neil G. Stevenson、Timothy J. Donohoe
DOI:10.1021/jacs.8b07776
日期:2018.9.26
An iridium catalyzed method for the synthesis of functionalized cyclohexanes from methyl ketones and 1,5-diols is described. This process operates by two sequential hydrogen borrowing reactions, providing direct access to multisubstituted cyclic products with high levels of stereocontrol. This methodology represents a novel (5 + 1) strategy for the stereoselective construction of the cyclohexane core
A General Organocatalytic Enantioselective Malonate Addition to α,β-Unsaturated Enones
作者:Veit Wascholowski、Kristian Rahbek Knudsen、Claire E. T. Mitchell、Steven V. Ley
DOI:10.1002/chem.200800673
日期:2008.7.7
A general enantioselective organocatalytic conjugate addition procedure of a variety of malonates to alpha,beta-unsaturated enone systems is presented. The reaction is efficiently catalysed by the pyrrolidinyl tetrazole catalyst 1. Cyclic, acyclic and aromatic enones can be used and the reaction with ethyl malonates 3 b provides the Michaeladdition products in high yields with good to excellent enantioselectivities
Stereoselective synthesis of alicyclic ketones: A hydrogen borrowing approach
作者:Roly J. Armstrong、Wasim M. Akhtar、James R. Frost、Kirsten E. Christensen、Neil G. Stevenson、Timothy J. Donohoe
DOI:10.1016/j.tet.2019.130680
日期:2019.11
A highly diastereoselective annulation strategy for the synthesis of alicyclic ketones from diols and pentamethylacetophenone is described. This process is mediated by a commercially available iridium(III) catalyst, and provides efficient access to a wide range of cyclopentane and cyclohexane products with high levels of stereoselectivity. The origins of diastereoselectivity in the annulation reaction
Simple chiral sulfonamide primary amine catalysed highly enantioselective Michael addition of malonates to enones
作者:Chunhua Luo、Yu Jin、Da-Ming Du
DOI:10.1039/c2ob07191f
日期:——
A chiral sulfonamide primary amine-organocatalysed, highly enantioselective Michael addition of malonates to enones has been developed. This reaction afforded the corresponding products in excellent yields (up to 99%) and excellent enantioselectivity (up to 99% ee).