Magnesium Monoperphthalate (MMPP): a Convenient Oxidant for the Direct Rubottom Oxidation of Malonates, β-Keto Esters, and Amides

A mild and convenient protocol for the alpha-hydroxylation of alpha-substituted malonates, beta-ketoesters, and beta-ketoamides is disclosed. Cheap and stable magnesium monoperphthalate (MMPP) was effective for a first direct alpha-hydroxylation protocol of the Rubottom oxidation, providing tartronic esters, cyclic alpha-hydroxy beta-ketoesters and amides in good to high yields, when working at room temperature and in ethanol as the solvent. The protocol has been successfully scaled up to gram quantity.

Automated summary

A mild and convenient protocol using cheap and stable magnesium monoperphthalate (MMPP) as the oxidant was developed for the alpha-hydroxylation of alpha-substituted malonates, beta-ketoesters, and beta-ketoamides. The protocol allows for the synthesis of various compounds in good yields at room temperature.