COORDINATING SULFONYL SUBSTRATES IN METAL-CATALYZED REACTIONS

Metal-coordinating heteroaryl sulfonyl groups, such as the 2-pyridylsulfonyl and the 8-quinolylsulfonyl group, allow the control of the reactivity and stereoselectivity of a great variety of metal-mediated reactions. This concept is rather general and has been applied for the activation of vinyl sulfones and N-sulfonyl imines, as well as in the direct C-H functionalization of N-H heterocycles. In particular, this kind of coordinating group has played a key role in the enantioselective Rh-catalyzed addition of boronic acids and Cu-catalyzed reduction of 2-pyridyl vinyl sulfones, the Cu-catalyzed addition of organozinc reagents, and the direct Mannich reaction of glycinate imines to N-heteroarylsulfonyl imines. In addition, a general procedure for the Pd-catalyzed C-2 alkenylation of N-(2-pyridylsulfonyl) indoles and pyrroles has been developed.