The photoinduced decarboxylative 1,6-addition of para-quinone methides with α-keto acids in an eco-friendly approach to α,α′-diarylated ketones is developed. This reaction proceeds smoothly with a broad substrate scope in the presence of cheap photocatalysts. Some of α,α′-diarylated ketones were applied as fluorescent dyes into the fluorescence spectrum and live-cell imaging.