Two new single-component, highly cross-linked polymeric materials have been developed that are capable of undergoing repeated cycles of mending. On the basis of the thermally reversible Diels-Alder (r-DA) cycloaddition reaction, these materials are comprised of a dicyclopentadiene core which acts as both diene and dienophile in the r-DA reaction. Polymer specimens have been prepared from two monomeric units, monomers 400 and 401, and the thermal and mechanical properties of these materials have been studied via differential scanning calorimetry, dynamic mechanical analysis, and three-point bending, compression, and fracture tests. After fracture, these hard, colorless, transparent materials are capable of thermal mending at 120°C, effectively healing cracks formed in the specimen.

Chiral, facial tris-cyclometalated Ir(III) complexes, fac-Delta-Ir(pppy)(3), fac-Lambda-Ir(pppy)(3), fac-Lambda-IrL (where pppy is (8R,10R)-2-(2'-phenyl)-4,5-pinenopyridine and L is a tripodal ligand comprising three pppy moieties connected through a mesityl spacer) have been synthesized and characterized. In IrL, NMR and CD studies indicate that only one diastereomer is formed, with the Lambda configuration at the metal center, whereas enantiopure pppy yields the fac-Lambda- and the fac-Delta-stereoisomer in a ratio 2:3. fac-Lambda-IrL was structurally characterized using X-ray crystallography. The luminescence properties including CPL, of the three complexes and their sensitivity to dioxygen were examined.