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A reliable and practical procedure for FeCl 3 -promoted ester cleavage has been developed. Lewis acids including TiCl 4 , ZnO and FeCl 3 etc. were investigated as promoters for O-alkyl cleavage of carboxylic acid ester. Under optimal reaction conditions, FeCl 3 (1.5 equiv.) was found to possess the highest activity and efficiently enhanced dealkylation of aryl esters, alkyl esters and aromatic heterocyclic esters to give their corresponding carboxylic acids in 54-98% yield, the method provides a complementary access to dealkylation of ester under neutral condition.

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An interesting Cu−Co/GO composite with special high organic content was accidentally fabricated for the first time via a one-pot solvothermal method in the mixed solvent of isopropanol and glycerol. The Cu−Co/GO composite was calcined separately in three different atmospheres (air, nitrogen, and argon) and further investigated by a series of characterization techniques. The results indicate that the spinel phase nano-CuCo 2 O 4 composite, nanometal oxides (CuO and CoO), and nanometal mixture of Cu and Co were unexpectedly formed after calcination in air, N 2 , and Ar atmospheres, respectively, and the possible reaction mechanism was discussed. The specific mass losses of the Cu−Co/GO composite calcined in air, N 2 , and Ar atmospheres were 28.14 %, 21.68 %, and 23.76 %, respectively. The catalytic decomposition performances of the as-prepared samples for cyclotrimethylenetrinitramine (RDX) and the mixture of nitrocellulose (NC) and RDX (NC + RDX) were investigated and compared via DSC method, and the results demonstrate that Cu−Co/GO composites obviously decrease the thermal decomposition temperature of RDX from 242.3 to 236.5 (before calcination), 238.6 (air), 235.8 (N 2 ), and 228.6 °C (Ar), respectively. Cu−Co/GO(Ar) composite exhibits the best catalytic decomposition performance among all samples, which makes the decomposition temperature of RDX and NC + RDX decrease by 13.7 and 4.9 °C and the apparent activation energy of decomposition for RDX decrease by 110.1 kJ/mol. The enhanced catalytic performance of Cu−Co/GO(Ar) composite could be attributed to the smaller particle size, better crystallinity, and specific welldispersed metal atoms, whereas the Cu−Co/GO(air) composite after air calcination presents a bad catalytic performance due to the removal of GO.

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