New porphyrins: synthesis,characterization, and computational studies

Molecular Diversity - New trans-A2B2-porphyrins substituted at phenyl positions were synthesized from 4-methylphthalic acid as a starting material through sequential multistep reactions. These...     

Aerial oxidation of bisnaphthols to spironaphthalenones by a recyclable magnetic core-sell nanoparticle-supported TEMPO catalyst

Aerial oxidative cyclization of bisnaphthols to their corresponding mixture of two isomeric spirans 3 and 4 has been carried out using a catalytic amount of magnetic core-shell nanoparticle-supported TEMPO (MNST) combined with a small amount of FeCl₃·6H₂O. This catalytic system consistently has the advantages of moderate to good yields, low reaction times, mild and convenient conditions, simple experimental and work-up procedure, and of being environmentally benign and highly economic. The magnetically separable MNST catalyst makes it possible for it to be recovered and recycled for several times without significant loss of activity.     

Retrievable magnetic copper ferrite nanoparticles: an efficient catalyst for air oxidative cyclization of bisnaphthols

Herein, a green and efficient heterogeneous and photocatalytic system for the oxidation of bisnaphthols in acetonitrile under light-emitting diode will be presented. In this reaction, aerial oxygen and H₂O₂ have been used as oxidant in the presence of copper ferrite nanoparticles and N-hydroxyphthalimide as an organic co-catalyst. Copper ferrite nanoparticles were magnetically separated, the efficiency of which remained nearly unchanged up to five cycles. Magnetic copper ferrite nanoparticles were synthesized by sol–gel method and characterized by XRD, FT-IR, SEM, TEM, VSM and DRS analysis. In this project, both sets of diastereomers were formed.

Graphical abstract

Catalytic system for the oxidation of bisnaphthols.