Organocatalytic Conversion of 1,2‐Disubstituted Epoxides to Cyclic Carbonates at Room Temperature and 1 Bar CO ₂

Herein, we report a homogeneous, recyclable organocatalyst that converts a broad range of 1,2–disubstituted epoxides and CO 2 into cyclic carbonates at 25 °C and 1 bar CO 2 . Rational placement convergence of four cooperative hydrogen bond donors adjacent to an ammonium–iodide nucleophile enables high catalytic activity and near perfect diastereoretention across diverse, poorly reactive 1,2–disubstituted epoxides. The catalyst is readily synthesized, metal–free, and maintains its performance over five consecutive recycles. Density functional theory (DFT) calculations reveal that dual–site H–bond pre–activation lowers every barrier along the reaction pathway and reduces the cyclization (RDS) barrier by approximately 1.4 kcal/mol relative to a less–convergent analogue, providing a clear mechanistic basis for the enhanced reactivity. This study demonstrates that cooperative, convergent H‐bond design is a powerful strategy for enabling ambient‐pressure organocatalytic CO 2 fixation into cyclic carbonates using highly unreactive internal epoxides, thereby offering generalizable design principles for sustainable and metal‐free CO 2 ‐utilization catalysis.