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A series of tetra(biphenyl-4-yl)phthalimide (TBPPI) derivatives with different N-substituents (n-butyl, phenyl, p-methyl phenyl, and p-acetyl phenyl moieties for compounds 7–10, respectively) were prepared to examine their fluorescent behavior under various conditions. The chemical structure of compound 7 has been successfully confirmed by single crystal X-ray diffraction analysis. The photoluminescence (PL) spectra in different ratios of CH2Cl2/EtOH mixture solutions revealed that compounds 7 and 8 exhibited both aggregation-induced emission (AIE) and aggregation-caused quenching (ACQ) behaviors, while compounds 9 and 10 displayed AIE and aggregation-induced emission enhancement (AIEE) properties, respectively.

Using 2,2-dimethyl cyclohexanone as the starting compound, (+)-antrocin and its diastereomer have been synthesized. The absolute stereochemistry of (-)-antrocin, a natural sesqui-terpenoid and an antagonist in some types of cancer cells, was clarified using the character data of (+)-antrocin. The synthetic procedure involved two key steps: (1) the reaction of vinyl magnesium bromide with 2,2-dimethyl-6-t-butyl-dimethyl-silyoxy-methyl-1-cyclo-hexanone to give a vinyl cyclohexanol derivative and (2) a highly stereoselective intramolecular Diels-Alder (IMDA) reaction of the camphanate-containing triene intermediate. The relative energy levels of the possible transition states of the IMDA reaction of the camphanate-containing triene were obtained from density functional theory calculations, proving the stereospecific formation of the target molecule.

Addition reaction of 3,4-dihydroisoquinolines with γ-hydroxy-α,β-unsaturated ketones furnished a variety of diastereomerically pure oxazolo[2,3-a]tetrahydro-isoquinolines, which could be purified by either recrystallization or solvent evaporation. The reaction proceeded smoothly under “green” conditions without an additive and catalyst, giving the target molecules in good to excellent yields.