Of note, when 1-phenyl-1,3-diene was subjected to the standard photocatalysis system, although the hydroxyldiazomethylation of 1,3-diene could occur to deliver the desired product 5-26 (35%), the reaction site were limited to 3,4-bisfunctionalization of terminal C=C double bonds. Finally, evaluating the reactivity of and Ar atmosphere in a sealed tube in a sealed tube, followed by flash chromatography on SiO 2 .