Daisuke Yamamoto
Kitasato University, Japan
Title: Manganese-catalysed hydroperoxidation of carbon–carbon double bonds using molecular oxygen present in air and hydroxylamine under ambient conditions
Biography
Biography: Daisuke Yamamoto
Abstract
Developing a new methodology for transition metal-catalysed oxidation reactions has been extensively studied in the recent decade, and molecular oxygen is essentially recognised as an ideal oxidant. Despite developing several elegant oxidation processes involving molecular oxygen as a sole oxidant, methodologies for directly incorporating molecular oxygen into organic substrates remains a major challenge in synthetic chemistry. In continuation of our studies on manganese-catalysed oxidative reactions, we have found that manganese(III) acetylacetonate is a highly efficient catalyst for hydroperoxidation of carbon-carbon double bonds of enynes as well as styrene derivatices using N-hydroxyphthalimide, N-hydroxybenzotriazole or N-hydroxysuccinimide under mild reaction conditions. This reaction proceeded at room temperature through the direct incorporation of molecular oxygen present in air. The required catalytic loading of manganese(III) acetylacetonate is extremely low (generally 0.02–0.5 mol%, and a minimum of 0.001 mol%). On the basis of this knowledge, we recently reported a manganese-promoted oxidative cyclisation of unsaturated oximes to provide 4,5-dihydroisoxazoline alcohols. In addition, we applied our method to the synthesis of hydroxamic acid, which is a promising antitrypanosomal agent for the management of Chagas disease. In the presentation, we will also discuss the further studies.