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Alcohols are a class of green chemicals in many aspects.1 In recent years,as frequently highlighted by the experts in the area,by employing the borrowing hydrogen or hydrogen autotransfer methodology (path a),1a-g alcohols have been extensively used as the alkylating reagents for the alkylation of amines and amides for the synthesis of the versatile amine derivatives.However,severe drawbacks still remain in these methods.In contrast,by using Wilkinson’s catalyst,we accidently found that air played a crucial role in the Rh-catalyzed N-alkylation reaction,2a which subsequently led to a general,more effective,and more advantageous air-promoted metal-catalyzed N-alkylation method and the discovery of a novel aerobic relay race mechanism in the aerobic N-alkylation reactions (path b)2b that has never been noticed and proposed in the metal-catalyzed N-alkylation of amines/amides with alcohols.1a-g Mechanistic studies revealed that the initial alcohol activation to aldehydes is the rate-limiting step of the whole reaction (path b,step i),and that metal-catalyzed aerobic alcohol oxidation is a more effective and greener alcohol activation alternative.Therefore,by simply carrying out the reactions under air,many simpler,cheaper,more available,and ligand-free metal catalysts,even the non-noble metal oxdides such as MnO2,2c can also be used as the catalyst,revealing the advantages of the new method.