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A heterogeneous iron-based catalyst for the aerobic oxidative cleavage of C−C bonds in alcohols to access esters was developed. Various alcohols including inactive long-chain alkyl aryl alcohols as well as β-O-4 lignin model compounds can be smoothly converted to the corresponding esters with molecular oxygen as the oxidant. Moreover, the present catalyst system can successfully degrade organosolv lignin. Base additives are not required except for inactive long-chain alkyl aryl alcohols. The catalyst exhibits good recyclability and can be easily recycled and reused up to seven times without a significant loss of catalytic activity. Characterization and control experiments confirmed that iron nanoparticles are mainly responsible for this reaction. Preliminary mechanism studies indicate that a sequential oxidation process exists in the reaction pathway.

The Cu/ABNO-catalyzed aerobic oxidative coupling of diols and primary amines to access N-substituted pyrroles is highlighted (ABNO = 9-azabicyclo[3.3.1]­nonane N-oxyl). The reaction proceeds at room temperature with an O2 balloon as the oxidant using commercially available materials as the substrates and catalysts. The catalyst system is characterized by a broad range of substrates and a good tolerance to sensitive functional groups. The gram-scale experiment proves this system’s practicability.

An efficient strategy for the oxidative cleavage of C=C bonds in olefins to form esters with one or multiple carbon atoms less over heterogeneous cobalt/nitrogen-doped carbon catalyst with dioxygen as...

An efficient and environmentally friendly methodology for the direct synthesis of α,β‐unsaturated ketones by cross‐coupling of secondary alcohols and aldehydes is developed. The transformation is based on Fe(acac)3‐catalyzed Oppenauer oxidation and Claisen‐Schmidt reaction, in which aldehydes are used as oxidants to oxidize secondary alcohols to ketones, and then in situ condensation with aldehydes to form α,β‐unsaturated ketones. The reaction proceeds under base‐free conditions with a wide range of substrates and good compatibility of functional groups. Gram‐scale experiments show the good applicability of this method.