Structure activity relationships of secondary amines in iminium ion catalysis

Recent reports have shown that the use of cyclic five membered nitrogen contg. heterocycles are effective catalysts for the asym. iminium ion catalyzed Diels-Alder, 1;3+23; and 1;4+33;-cycloaddns., as well asym. Michael addns. with a range of nucleophiles. We have become interested in developing new catalyst architectures to accelerate this class of transformation to provide more efficient systems than those reported while gaining a intimate understanding of the reaction mechanism. It has been proposed that the rate detg. step of the catalytic cycle is iminium ion formation. Based upon the concept of introducing a heteroatom α- to the reactive nitrogen to increase its nucleophilicity α-effect) we will report on a variety of templates with which we have developed a structure-reactivity relationship model. In conjunction with our synthetic studies we will also report on our theor. and mechanistic findings into the catalytic cycle and the relationship between amine structure and catalyst efficiency. [on SciFinder(R)]