In conclusion, we have developed a general protocol for chlorinating cyclopropanes, olefins, and activated C-H bonds using the direct photoexcitation of the Willgerodt reagent (6a). The conditions are mild and the reaction practical to set up, with a wide range of functional groups tolerated. Additionally, we demonstrated that photo-mediated chlorination using Iodine(I/III) catalysis is possible, which serves as a complementary approach to the stoichiometric use of the Willgerodt reagent (6a). Taking advantage of the easily accessible benzylic chlorides, we have developed a one-pot protocol for further substitution with C, N, O, and S nucleophiles, and for repurposing the aryl iodide byproduct in a reductive cross-coupling. Our work provides a practical approach to functionalize cyclopropanes, olefins, and activated C-H bonds via the formation of organo-chlorine intermediates, and we believe it will be, therefore, of interest for accessing useful building blocks in synthetic and medicinal chemistry.