Protio-iminium ions

Recently, Jacobsen developed a new strategy for inducing enantioselectivity in reactions of protio-iminium ions, wherein a chiral urea 95 interacts with the highly reactive intermediate through a network of noncovalent interactions. This interaction leads to an attenuation of the reactivity of the iminium ion and allows high enantioselectivity in the Povarov reaction, giving lactam-substituted tetrahydroquinoline derivatives 98 in excellent enantioselectivities and diastereoselectivities. ... 

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