Introduction of an isoxazoline unit to the β-position of porphyrin via regioselective 1,3-dipolar cycloaddition reaction.

Isoxazoline-linked porphyrins have been synthesized by a regioselective 1,3-dipolar cycloaddition reaction between vinylporphyrin and nitrile oxides. The steric interaction directed the reaction trajectory, in which only the product with a link between the 5-position of the isoxazoline and the β-position of porphyrin was observed. The isoxazoline-porphyrins , have been characterized by absorption, emission, H NMR and mass spectra. Later, the crystal structure of was obtained and confirmed the basic features of the NMR-derived structure. Furthermore, a pair of enantiomers of presented in the crystal, which formed a dimeric complex through intermolecular coordination between the Zn center and the carbonyl group of the second molecule.