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Two anthracene-based complexes [Ir(pbt)2(aip)]Cl (1) and [Ir(pbt)2(aipm)]Cl (2) have been synthesized based on the ligands aip = 2-(9-anthryl)-1H-imidazo[4,5-f][1,10]phenanthroline, aipm = 2-(9-anthryl)-1-methyl-imidazo[4,5-f][1,10]phenanthroline, and pbtH = 2-phenylbenzothiazole in order to explore both the influence of the substituent group R1 (R1 = H in 1 and CH3 in 2) on photo-oxidation activity and photo-oxidation-induced luminescence. Both 1H NMR spectra and ES mass spectra indicate that the anthracene moiety in complex 1 can be oxidized at room temperature upon irradiation with 365 nm light. Thus, this complex shows photo-oxidation-induced turn-on yellow luminescence. Compared to 1, complex 2 incorporates an R1 = CH3 group, resulting in very weak photo-oxidation activity. On the basis of experimental results and quantum chemical calculation, we report the differences between 1 and 2 in both photo-oxidation behavior and the related luminescence modulation and discuss the relationship between photo-oxidation activity and substituent group R1 in these complexes.

An enantioselective asymmetric annulation of 2-formylboronic acids with internal alkynes has been realized using a chiral phosphinooxazoline/palladium(II) catalyst. The reaction tolerates a variety of alkynes including the relatively inert diaryl substituted internal ones. A wide range of optically active 2,3-disubstituted indenols was afforded in high yields with good to excellent enantioselectivities (up to 99% yield and 99% ee).

A new palladium-catalyzed domino approach for the synthesis of attractive spirocyclic indolines and dihydrobenzofurans was developed. The reaction proceeds through a sequential intramolecular Heck spirocyclization, remote C-H activation, and diazocarbonyl carbene insertion. Various spiroindolines and spirodihydrobenzofurans containing two quartenary carbon stereocenters were readily obtained in good to excellent yields. A preliminary study of asymmetric spirocyclization using chiral monophosphoramidite as a ligand was also conducted, enabling access to highly valuable chiral spiroindolines with up to 80% ee.

An asymmetric dual-metal relay catalysis strategy that combines Rh/chiral sulfur-olefin-catalyzed enantioselective 1,2-addition with a Pd-catalyzed intramolecular C-O coupling has been developed. The method allows rapid and efficient synthesis of quaternary carbon-containing gem-diaryl benzofuran-3(2H)-ones in good yields in a highly enantioselective manner (up to 99% ee) through a simple one-pot cascade reaction.

A rhodium-catalyzed stepwise asymmetric 1,4- and 1,2-addition of arylboronic acids to α,β-unsaturated cyclic N-sulfonyl ketimines has been developed, providing a wide range of gem-diaryl-substituted chiral benzosulfamidates with high optical purities. C1-Symmetric chiral diene and branched chiral sulfur-olefin ligands were sequentially utilized in this double-arylation process for high stereocontrol. Further synthetic utility offers new opportunities for the facile construction of otherwise difficult to access polycyclic heterocycles.

The first example of nickel-catalyzed asymmetric Ullmann coupling of bis-ortho-substituted arylhalides is described. With the chiral BINOL-based monodentate phosphoramidite ligand, the reaction allows atropoenantioselective synthesis of a series of axially chiral tetra-ortho-substituted biaryl dials. By taking advantage on this asymmetric Ullman coupling as a key stereogenic axis-forming reaction, the formal synthesis of (+)-isoschizandrin was accomplished.

An interesting aldehyde- and ketone-induced intermolecular tandem decarboxylation-coupling (Csp(3)-Csp) catalyzed by copper with use of natural alpha-amino acids as starting materials is developed under neutral conditions with the production of CO(2) and H(2)O as the only byproducts. Various functionalized nitrogen-containing compounds were obtained by this method. In these processes, interesting regioselectivites of the alkylation were observed, which has been rationalized by the relative stability of proposed resonance structures based on computation methods.