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The cobalt–salen complex (C1:[(salen)Co3+(OAc)]; salen= N,N′-bis(salicylidene)ethylenediamine, OAc=acetate) was found to efficiently promote the hydration of terminal alkynes to give methyl ketones in the presence of the H2SO4 cocatalyst. In addition, the one-pot transformation of alkynes into chiral alcohols through tandem catalysis by catalyst C1 coupled with a ruthenium–TsDPEN complex (C3: [(R,R-TsDPEN)Ru2+(cymene)]; TsDPEN=(1R,2R)-N-(p-toluenesulfonyl)-1,2-diphenylethylenediamine, cymene=1-methyl-4-(1-methylethyl)benzene) catalyst was realized with excellent yields and enantioselectivities.

A benzimidazole-based nonheme manganese complex efficiently catalyzes benzylic, aliphatic C–H as well as tertiary C–H oxidation with hydrogen peroxide as the oxidant in the presence of acetic acid as additive. 18O labeling experiments suggest the reaction may proceed via a high-valent manganese-oxo intermediate.

The 5-endo chlorocycloetherification proceeds rapidly under catalyst-free-conditions to give β-chlorotetrahydrofurans in high yields.

using an easily available quaternary ammonium salt derived from cinchonine as organocatalyst

A novel series of tetradentate N4 ligands is prepared and successfully applied in the Fe-catalyzed asymmetric epoxidation of a diversity of di- and trisubstituted enones.

A variety of magnetic nanoparticles of ferrite complex oxides is prepared and tested in the N-arylation of imidazole.

the “Hundred Talents Program” of the Chinese Academy of Sciences and the National Natural Science Foundation of China (20873166;21073210;21133011)

The methodology works efficiently for numerous secondary alcohols including benzylic alcohols with ortho substituted aromatic rings.

A series of biaryl-bridged salalen ligands together with their titanium complexes have been designed and synthesized. The Ti complexes could serve as highly efficient catalysts for the asymmetric epoxidation of a wide range of olefins, giving the corresponding epoxides with high ee values.

Both enantiomers of nitriles (III) can be prepared by modifying the salen-titanium catalyst.

The catalyst can be conveniently recovered by an external magnet and reused several times without loss of its catalytic activity.

Best results are achieved with iodides whereby, substrates with electron-withdrawing groups like the nitro derivative (Ib) give the desired products even in the absence of the catalyst system.

Two new tetradentate ligands derived from salen have been prepared and their titanium complexes are used as chiral catalysts in the enantioselective silylcyanation of aldehydes, which give the silyl ethers of cyanohydrins in moderate to good enantiomeric excesses.

A new type of chiral tridentate ligands were prepared and their Zn complexes were examined for the asymmetric Friedel-Crafts alkylation of indoles with nitroalkenes, which gave rise to good yields and moderate enantioselectivities.

A variety of olefins is efficiently transformed to the corresponding epoxides by Ti-catalyzed asymmetric reaction using novel salan/salalen ligands, e.g. (I) or (II).

A novel series of chiral tetradentate N4 ligands together with their manganese complexes have been designed and synthesized. With 1 mol % manganese catalyst loading, the enantioselective epoxidation of olefins proceeds with nearly full conversion and enantiomeric excess values of up to 89 % for the first time.

The use of (NHC)CuI complex in combination with a N-heterocyclic carbene precursor as catalyst for the double carbonylation of aryl Iodides and secondary amines solves the problem of using the precious metal Pd and phosphine ligands. The new protocol requires a nonprecious metal catalyst and has greater generality than those previously reported.