Solar-driven　carbon　dioxide　(CO2)　reduction　integrated　with　selective　organic　synthesis　proposes　a　sustainable　paradigm　to　achieve　carbon　neutrality　concomitantly　with　value-added　fuels　and　chemicals　production.　Here,　we　report　the　synergistic　coupling　reaction　of　CO2　reduction　and　amines　oxidation　to　syngas　and　secondary　amines　over　Cu　doped　CdS　quantum　dots　(Cu:CdS　QDs)　under　visible　light.　This　system　is　compatible　with　various　amines　to　afford　the　corresponding　secondary　amines　with　outstanding　selectivity.　Notably,　the　syngas　CO/H2　ratio　can　be　obtained　in　a　window　from　1:2　to　2:1　by　altering　the　Cu　doping　content.　Mechanistic　studies　unveil　that　doped　Cu　not　only　improves　the　charge　separation　efficiency,　but　also　serves　as　active　sites　for　the　adsorption/activation　of　CO2,　thus　adjusting　the　syngas　ratio.　This　work　is　envisaged　to　enable　a　viable　strategy　for　the　rational　design　of　transition　metal-doped　semiconductor　QDs　toward　the　co-production　of　syngas　and　high-value　chemicals　in　one　photoredox　cycle.