Rh-catalyzed asymmetric hydrogenation of α-aryl-β-alkylvinyl esters with chiral ferrocenylphosphine-phosphoramidite ligand
作者:Chao Dong、Dao-Sheng Liu、Lei Zhang、Xiang-Ping Hu
DOI:10.1016/j.tetlet.2020.152763
日期:2021.2
An enantioselective Rh-catalyzedhydrogenation of E/Z mixtures of trisubstituted vinyl esters has been disclosed. With a combination of [Rh(COD)2]BF4 and a structurally fine-tuning chiral ferrocenylphosphine-phosphoramidite ligand as the catalyst, a variety of E/Z mixtures of α-aryl-β-alkylvinyl esters have been successfully hydrogenated in high yields and with good to high enantioselectivities (up
Hypervalent Iodine(III)‐Catalysed Enantioselective α‐Acetoxylation of Ketones
作者:Tobias Hokamp、Thomas Wirth
DOI:10.1002/chem.202000927
日期:2020.8.17
An enantioselective catalytic synthesis of α‐acetoxylated ketones through I(I)/I(III) catalysis using a resorcinol/lactamide‐based chiral iodoarene is reported. Catalyst turnover by in situ generation of the active iodine(III) derivative is achieved by oxidation with mCPBA in the presence of acetic acid. The prior transformation of ketones to easily accessible acetyl enol ethers is beneficial and yields
Enantioselective Iodine(III)-Mediated Synthesis of α-Tosyloxy Ketones: Breaking the Selectivity Barrier
作者:Benoit Basdevant、Claude Y. Legault
DOI:10.1021/acs.orglett.5b02501
日期:2015.10.2
levels of enantioselectivity are reported for the synthesis of α-tosyloxy ketones, using enolesters and chiral iodine(III) reagents. The reaction can be performed under both stoichiometric and catalytic conditions. These results suggest widely different reaction mechanisms for the reaction of ketones versus enolesters, supporting recent computational insights.
Study of the Reactivity of [Hydroxy(tosyloxy)iodo]benzene Toward Enol Esters to Access α-Tosyloxy Ketones
作者:Benoit Basdevant、Claude Y. Legault
DOI:10.1021/acs.joc.5b00948
日期:2015.7.2
The reactivity of enol esters toward [hydroxy(tosyloxy)iodo]benzene (HTIB) was assessed. These substrates were found to be rapidly converted in high yields to their corresponding α-tosyloxy ketones. This transformation demonstrates that these substrates can act as ketone surrogates. The scope of the method was investigated and aromatic, aliphatic, and cyclic enol esters were found to be suitable substrates