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
Use of a Semihollow-Shaped Triethynylphosphane Ligand for Efficient Formation of Six- and Seven-Membered Ring Ethers through Gold(I)-Catalyzed Cyclization of Hydroxy-Tethered Propargylic Esters
The formation of six‐ and seven‐membered ring ethers from hydroxy‐tethered propargylic esters was efficientlycatalyzed by a cationic gold(I) complex with a semihollow‐shaped triethynylphosphane ligand. This gold catalysis showed a tolerance toward the reactions of primary, secondary, and tertiary alcohol substrates with various substitution patterns. A sterically congested 2,2,6,6‐tetraalkyl‐substituted
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
A method for producing a cyclic ether represented by formula (2) includes reacting a 2-hydroxy cyclic ether, represented by formula (1), with hydrogen in the presence of a catalyst.
A process for producing a polyhydric alcohol includes a step (I) of hydrogenating hemiacetal having a specific structure to obtain a reaction solution (I), and a step (II) of adding water to the reaction solution (I) obtained in the step (I) and further conducting hydrogenation.