Ruthenium(II)-Catalyzed Hydroarylation of Maleimides Using Carboxylic Acids as a Traceless Directing Group

An efficient Ru­(II)-catalyzed
hydroarylation of maleimides with
ready-stock aryl carboxylic acids has been developed based on weak
carboxylate-directed ortho-C–H alkylation
and concomitant decarboxylation processes, fabricating 3-aryl succinimides,
a recurrent scaffold in drug molecules, in high yields (up to 97%).
The protocol features operational simplicity, avoids the need for
precious metal additives/oxidants, and offers broad substrate scope
with formal meta- and para-selectivities.
It represents the first example of Ru­(II)-catalyzed direct arylation
of maleimides with unbiased benzoic acids.