Modular access to chiral cyclopentanes via formal [2+2+1] annulation enabled by palladium/chiral squaramide relay catalysis

An enantio- and diastereodivergent [2+2+1] annulation reaction of allyl ketones, acidic methylene compounds, nitroalkenes to assemble highly functionalized cyclopentanes from readily available substances enabled by asymmetric relay catalysis chiral bifunctional squaramide palladium complex has been established. This method showcases that ketones can serve as latent 1,2-dication synthons via a linear-selective allylic C–H functionalization sequential 1,4-conjugated addition, enabling the rapid assembly cyclopentane skeleton with broad scope nucleophiles nitroalkenes. Notably, catalyst engages in both intermolecular intramolecular Michael addition reactions accompanying kinetic resolution behavior amplify enantioselection. In stereodivergent synthesis diastereomers resultant derivatives is also accessible simple manipulation base.