One-Pot Multi-Component Asymmetric Cascade Reactions Catalyzed by Soluble Star Polymers with Highly Branched Non-Interpenetrating Catalytic Cores

Non-interpenetrating star polymer catalysts designed to mimic the site isolation characteristics of enzymes enable the one-pot combination of multiple otherwise incompatible catalysts for asymmetric cascade reactions that involve iminium, enamine, and H-bonding catalysis. Control experiments replacing star polymer catalysts with the corresponding small molecule or linear polymer analogues lead to little or no cascade reaction. Our strategy also allows straightforward access to all possible stereoisomers of the cascade product individually by proper choice of catalyst chirality. To our knowledge, this work represents the most sophisticated study of soluble polymers for site isolation, enzyme-like catalysis that generates cascade products with multiple chiral centers.