Ligand Promoted Pd-Catalyzed High para -Selective C-H Olefination.

Achieving high para -selective C-H functionalized products of benzoic acid derivatives using a designed template is still a daunting challenge because the carbonyl group also could coordinate with metal to activate the ortho -C-H bond. Herein, we report the ligand promoted high para -selective C-H olefination of benzoic acid derivatives; we screened a series of ligands increasing the ratio of p :others from 62:38 to 96:4. This work may find application in the construction of para -substituted benzoic acid derivatives.