Synergistic solvent-catalyst paradigm for sustainable aerobic allylic C-H functionalization.

Achieving sustainable catalytic transformations requires synergistic optimization of solvent systems, catalytic motifs and energy inputs. Herein, we report a synergistic Pd/hydroquinone catalytic system that enables aerobic allylic C-H functions under ambient conditions (room temperature to 50°C, air) with high turnover frequency (TOF), using ethanol/water as a green medium. This strategy achieves unparalleled synthetic efficiency and demonstrates remarkable versatility across two pivotal transformations (alkylation and amination) involving over 90 products (up to 96% yield). It also delivers exceptional stereocontrol (up to 93% ee for quaternary stereocenters) and enables advanced allylic transformations within a green framework through additional synergistic catalysis. By integrating solvent engineering with cooperative catalysis, we have developed a scalable platform for the synthesis of allylic functionalized molecules with pharmaceutical interests, demonstrating how molecule-level innovation can drive sustainable industrial transformation.