 The study presents a simplified photochemical system that utilizes catalytic amounts of iron, 3, halides as multifunctional reagents and air as a green oxidant to achieve cross-coupling between strong C, SP2, H-bonds and robust C, SP3, H-bonds, with high yields and commendable chemo and site selectivity. The iron halide acts as a multifunctional reagent that responds to visible light, initiates C-centered radicals, induces single electron oxidation to carbocations and participates in a subsequent Friedel-Crafts-type process, with the gradual release of radical species and carbocation intermediates being critical for achieving desirable reactivity and selectivity. This eco-friendly, cost-efficient approach offers access to various building blocks from abundant hydrocarbon feedstocks, demonstrating the potential of iron halides in sustainable synthesis. This article was authored by Chen Youli, Shiyeng Chen, Zikeyi and others.