Mn(OAc)3 induced C-4 arylations of quinazoline 3-oxides with arylboronic acids

The use of manganese triacetate as an oxidant component in the C-4 arylations of 2-aryl-quinazoline 3-oxides with arylboronic acids is reported. The new protocol was applied to prepare new 2,4-diarylated quinazoline 3-oxides in good to high yields. The method was shown to tolerate various substituents on both aromatic rings, and no complications as deoxygenation and rearrangement to quinazolin-4(3H)-one was observed.

Transition-Metal-Promoted Oxidative Cyclization To Give 1,2,4-Trisubstituted Carbazole Scaffolds

Herein, we describe the synthesis of a 1,2,4-trisubstituted carbazole core from 5-(1H-indol-3-yl)-3-oxopentanoic acid esters or amides. For oxidative cyclization, we tested two different approaches. First, we used manganese triacetate as a conventional moderate oxidizer to ensure the radical course of the reaction. Second, we examined the use of a more complex oxidizing agent I2/Me(OTf)3. In both cases, formation of a fused-ring carbazole system with a 2-hydroxyl and 1-carboxylic substituent were observed. In connection with the formation of an unexpected reaction intermediate, mechanistic aspects of the process were discussed.

Manganese triacetate as an efficient catalyst for bisperoxidation of styrenes

Bisperoxidation of styrenes with tert-butyl hydroperoxide in the presence of a catalytic amount of Mn(OAc)3.