Selective catalytic chlorination: key strategic pathways for renewable resources functionalization to transition away from fossil fuels.

Natural olefins, especially terpenic ones, are widely distributed in the plant kingdom as a renewable resource alternative to the petroleum-based hydrocarbon industry and a key strategic pathway toward net-zero emissions by 2050. Their structural complexity allows for conversion into valuable intermediates for fine chemicals, flavors, fragrances, pharmaceuticals and biofuels. Precise functionalization methods are essential to transform these natural products into useful building blocks, notably through regioselective functionalization of biogenic alkenes. Among the pathways, selective chlorination of terpenic olefins has garnered special interest, employing various synthetic approaches using potential chlorinating agents. This reaction affords a range of chlorinated products with strong electrophilic character, particularly allylic and vinylic chlorides as highly reactive intermediates in organic synthesis for applications in agrochemicals, bioactive compounds, polymers and pharmaceuticals. It is a key pathway for the valorization of biomass-derived terpenes into chiral building blocks, contributing to the circular economy and sustainable chemistry. This is a thorough and up-to-date review on the selective chlorination reaction, outlining (i) the general chemistry of olefin chlorination and chlorinating agents, (ii) systematic comparison of catalytic chlorination pathways, particularly Lewis acid (e.g., MCl x ) and process heterogenization, (iii) explored mechanisms, (iv) scale-up challenges, future perspectives and potential applications of chlorinated compounds.