AbstractA mild, asymmetric Heck–Matsuda reaction of five‐, six‐ and seven‐membered ring alkenes and aryl diazonium salts is presented. High yields and enantioselectivities were achieved using Pd⁰ and chiral anion co‐catalysts, the latter functioning as a chiral anion phase‐transfer (CAPT) reagent. For certain substrate classes, the chiral anion catalysts were modulated to minimize the formation of undesired by‐products. More specifically, BINAM‐derived phosphoric acid catalysts were shown to prevent alkene isomerization in cyclopentene and cycloheptene starting materials. DFT(B3LYP‐D3) computations revealed that increased product selectivity resulted from a chiral anion dependent lowering of the activation barrier for the desired pathway.