Carboxylic acids, as a fundamental raw material, are widely used in the production of food preservatives, pesticides, dyes intermediates, coatings, plasticizers, spices, and a number of prescription drugs. In consideration that the significance of carboxylic acids are important fine chemicals in both laboratory and industry, the promoting synthetic processes of carboxylic acids has been presented. The green production of carboxylic acids is the direct oxidation of primary alcohols in one step. The selective oxidation reaction from these alcohols is one of the most fundamental chemical processes in organic synthesis. Traditionally, this chemical transformation is carried out by using stoichiometric, toxic and expensive oxidants such as HNO 3 , KMnO 4 , K 2 Cr 2 O 7 , etc., which would lead to a series of severe environmental problems because of excessive emissions of chemical waste. Compared with traditional oxidants, O 2 , as an abundant and green sustainable natural feedstock, is perfect for incorporation into value-added fine chemicals due to its easily available and environmentally benign advantages. There are a large number of methods developed for the oxidation of alcohols with molecular oxygen. Hence relatively noble metal-ligand complex homogeneous catalysts, commercially catalysts and base-based catalyst have been employed to achieve the synthesis of acids with molecular oxygen, where noble metallic catalysts and oxidation-neutralization operation procedures were necessary. Especially, the use of (super)stoichiometric amounts of strong bases leads to a series of environmental pollution issues. To date, using these cocatalysts and molecular oxygen gave well to excellent yield. For example, several groups developed the oxidation of alcohols catalyzed by TEMPO-based reagents and cocatalysts in the aerobic oxidation reaction (such as Fe(NO 3 ) 3 •9H 2 O/TEMPO/KCl). Many impressive achievements prompted us to consider other bromide-catalyzed oxidation methods.