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CO2 emissions have received a great deal of attention in recent years. The hydrogenation of CO2 to higher alcohols (HA) by heterogeneous catalysis is a promising artificial carbon cycle pathway, which has important significance for mitigating energy and environmental problems. Among the heterogeneous catalysts, supported catalysts exhibit unique catalytic activity due to their abundance of surface‐tunable active sites such as oxygen vacancies, surface acidic/basic sites, and active hydroxyl groups. Given the complexity in the CO2 hydrogenation reaction networks, however, it is very challenging to reveal the nature and role of unique interfaces/sites induced by oxide support. Herein, we review the progress of several common oxide supports in the CO2 hydrogenation to HA over the last decades, and illustrate the regulatory mechanisms of the oxide‐induced synergy on the activation of intermediates and the C−C coupling reactions. Based on this, we also discuss the present challenges associated with the HA synthesis from CO2 hydrogenation, as well as the thinking oriented on oxide support‐induced structure changes to improve the selectivity and productivity of HA. [ABSTRACT FROM AUTHOR]

Quinclorac is important precursor for pharmaceutical, agricultural, and synthetic chemistry. The state‐of‐art synthesis of quinclorac via condensation, chlorination and oxidative hydrolysis often uses homogeneous catalysts and strong acid oxidant agents to promote the catalytic oxidation, which requires huge manpower input for the late‐stage purification process and is usually environmentally unfriendly. In this work, we successfully fabricated a stable cobalt phthalocyanine (CoPc) Co‐based composite (CoPc/TiO2) by anchoring CoPc on the surface of TiO2 nanorods for the selective oxidation of 3,7‐dichloro‐8‐dichloro methyl quinoline (3,7‐D‐8‐DMQ) into quinclorac. More impressively, CoPc/TiO2‐2.5 %‐Mn‐Br exhibits a high selectivity of 91.9 % for the catalytic oxidation of 3,7‐D‐8‐DMQ to quinclorac in acetic acid, with a quinclorac yield of 86.4 %, which is approximately 2.43 times higher than that of pristine CoPc‐Mn‐Br. The obtained heterogeneous catalytic system shows good reusability. Detailed mechanistic investigations reveal that the system works through a free radical mechanism via the formation of Co2+/Co3+ redox cycles. This work provides a new understanding for the stabilization of reaction intermediates and facilitates the designs of catalysts for selective catalytic oxidation. [ABSTRACT FROM AUTHOR]