Boron/zinc exchange for the conjugate arylation of unsaturated Meldrum’s acid derivatives
作者:Micaela Jardim、Lucas L. Baldassari、Maria Eduarda Contreira、Angélica V. Moro、Diogo S. Lüdtke
DOI:10.1016/j.tet.2020.130967
日期:2020.12
approach for the conjugate arylation reaction of unsaturated Meldrum’s acid derivatives is reported. The reaction takes place through a Boron-Zinc exchange reaction between arylboronic acids and diethylzinc and the subsequent transfer of thus generated reactive aryl groups to the β-position of the double bond of the Meldrum’s derivatives. The compounds obtained are valuable synthetic intermediates and
<i>N</i>-Heterocyclic Carbene-Catalyzed Oxidation of Unactivated Aldehydes to Esters
作者:Brooks E. Maki、Karl A. Scheidt
DOI:10.1021/ol8018488
日期:2008.10.2
N-Heterocyclic carbenes catalyze the oxidation of unactivated aldehydes to esters with manganese(IV) oxide in excellent yield. The reaction proceeds through a transient activated alcohol, which when generated in situ allows for the selective oxidation of the aldehyde under mild conditions. These conditions successfully oxidize potentially epimerizable aldehydes and alcohols while preserving stereochemical