Abstract:
Carbon dioxide (CO
2) is an attractive green C1 resource due to its abundance, low cost, environmental friendliness, and renewability. These carboxylic acids are widely found in pharmaceutical molecules, natural products, and functional materials, serving as essential synthetic building blocks and intermediates with irreplaceable roles in pharmaceuticals, pesticides and chemicals. Therefore, the efficient transformation of CO
2 into high-value carboxylic acids by catalytic activation to construct C—O and C—C bonds precisely, not only has significant scientific research value, but also fits national goals of carbon peaking and carbon neutrality as well as the demands of the sustainable development strategy. Allylic alcohols and their derivatives (e.g., ally halides, allyl ester, etc.) are a class of easily accessible and structurally diverse synthons. Based on this, the article focuses on four kinds of allyl compounds including allyl alcohols, allyl halides, allyl esters, and allyl C—H compounds, and systematically reviews the research progress of their carboxylation reactions with CO
2 under different catalytic systems. The research indicates that transition metal complexes are the main catalysts in the developed system. Allyl alcohols and its derivatives undergo oxidative addition with transition metals to form delocalized π-allyl metal intermediates, which typically exhibit electrophilic character. Under reductive conditions, these intermediates can be transformed into nucleophiles that react with various electrophiles, including stable CO
2. So catalytic systems are mainly classified and expounded according to metal types and metal-free catalytic systems. We systematically summarize diverse activation modes—including thermal catalysis, photocatalysis, electrocatalysis, metal catalysis, and photo/electro/metal synergistic catalysis. The reaction mechanisms, substrate scope and regioselectivity control under different catalytic systems were deeply discussed, aiming to develop greener, more efficient and sustainable CO
2 conversion strategies.