VO(acac)(2)-CeCl(3) combo catalyst has been developed for chemoselective cyclocondensation cum oxidation under mild reaction conditions toward synthesis of a new class of optically pure compounds, 2-(2'-C-3',4',6'-tri-O-benzyl/methyl-glycal)-1H-benzimidazoles. It involves an operationally simple synthetic protocol efficient for the syntheses of a wide range of chiral benzimidazoles in high yields without formation of undesired 1,2-disubstituted and pseudoglycal byproducts. Vanadium(V) is found as active oxidant for the chemical processes which is investigated by UV absorption spectroscopy. Highly ordered one-dimensional low molecular mass organic nanostructured materials are fabricated by nanocrystallization of the chiral nanoscale building blocks. Theoretical calculation by the B3LYP/6-31G** level of theory of the glycal-based chiral benzimidazoles shows out of planar geometry of the 1H-anthra[1,2-d]imidazole-6,11-dione moiety, which is responsible for the strong self-aggregation to generate ultralong nanostructured materials. We have also found nice agreement between the theoretical results with the experimental observation in 2D-NOESY experiments. The photophysical property of the solid nanostructured materials is also reported.

A highly efficient strategy for chemoselective oxidation of aldoximes to nitrile oxides by iodosobenzene in neutral aqueous media is reported. Their in situ intermolecular 1,3-dipolar cycloaddition (1,3-DC) with olefins in nanometer aqueous micelles occurs with improved stereoselectivity and acceleration of reaction rate toward synthesis of new chiral synthons, 3-(2'-C-3',4',6'-tri-O-benzylglycal)-Delta(2)-isoxazolines and others. Construction of optically pure 2,8-dioxabicyclo[4.4.0]decene skeleta is performed by this green approach, and the stereochemistry of the new chiral center is predicted by B3LYP density functional theory.

The first ever breakthrough toward activation of β-ketoacetanilide and subsequent C-C and C-N bond-forming intermolecular-cascade cyclization processes is demonstrated by development of the unprecedented Lewis acid property of non-toxic FeCl(3)⋅6H(2)O. Aromatic, aliphatic, α,β-unsaturated, chiral sugar-based and chromone aldehydes were regio- and stereoselectively cyclized with acetoacetanilides toward construction of valuable N-containing highly functionalized 2-pyridones (see scheme for an example).

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Activation of π-bond with organic Lewis acid and cationic surfactant mediated direct transfer of halides to alkyne and alkene are demonstrated to afford α,α-dihaloketones and other valuable synthons with outstanding selectivities.

The powerful cyclization and tandem oxidation property of environmentally benign PhIO is developed for the first time, which leads to regiospecific [3+2]-tandem oxidative cyclization of imine at room temperature in rapid access to a new class of compounds, 1,2-functionalized 4,5-diarylimidazoles, in excellent yield with synthetic efficiency. Size, shape, and activity of the involved nanoreactors for the green approach built up from various surfactants are investigated. Spontaneous generation of low molecular mass self-aggregated organic materials, their cofacial one-dimensional packing, and interesting photophysical properties are reported.

A cascade cyclization involving union of three imines by an organocatalyst proline is established to afford new fused-tetrahydroimidazo[1,5-c]imidazol-7-ones with excellent regio- and stereoselectivity. Another dehydrogenative cyclization by union of two imines is developed using the Cu(OTf)(2)-Ag(2)O combo catalyst to furnish functionalized imidazoles.

Generation of azomethine imine and its scope in regioselective 1,3-dipolar cycloaddition (DC) of imine with PhIO toward highly substituted Delta(2)-1,2,4-triazoline, 1,2,4-triazole, and their fused, chiral, and sugar-based analogues are demonstrated.