This study presents a dinuclear Cu(I) molecular complex, CuBr–4PP, which efficiently catalyzes the electrochemical reduction of CO₂ to C₃H₇OH. The complex exhibits robust structural stability and high selectivity for C-C coupling, leading to the formation of valuable C₃ products. Operando surface-enhanced Raman scattering (SERS) and density functional theory (DFT) calculations provide insights into the C-C coupling mechanism, suggesting the formation of a C-C coupling intermediate between the two Cu centers. The molecular design guidelines derived from this discovery offer a promising approach for developing next-generation catalysts capable of generating multicarbon products from CO₂ reduction.This study presents a dinuclear Cu(I) molecular complex, CuBr–4PP, which efficiently catalyzes the electrochemical reduction of CO₂ to C₃H₇OH. The complex exhibits robust structural stability and high selectivity for C-C coupling, leading to the formation of valuable C₃ products. Operando surface-enhanced Raman scattering (SERS) and density functional theory (DFT) calculations provide insights into the C-C coupling mechanism, suggesting the formation of a C-C coupling intermediate between the two Cu centers. The molecular design guidelines derived from this discovery offer a promising approach for developing next-generation catalysts capable of generating multicarbon products from CO₂ reduction.