Selective CO2 uptake and vapor adsorption study within Sn(iv) porphyrin crystals

Abstract

A systematic investigation of the effect that simple substituents attached to the phenolic ring have on the stability and adsorption properties of the porous crystals of parent Sn(IV) porphyrin diphenolates is made. A family of three dimensional honey-comb-like supramolecular porous materials (SPMs) was obtained by crystallisation of three different discrete porphyrin diphenolates Sn(IV)tTTP(o-cresol)₂ (1), Sn(IV)tTTP(o-bromo)₂ (2), Sn(IV)tTTP(m-nitro)₂ (3). Their structures and crystalline integrity were studied using single crystal X-ray diffraction and powder X-ray diffraction techniques, respectively. Vapor adsorption measurements on Sn(IV)tTTP(o-cresol)₂ revealed a guest uptake capacity. Gas adsorption investigations of these materials demonstrates that this class of SPMs retains high thermal stability and permanent porosity with functional groups lining the pores, which makes this Sn(IV) porphyrin diphenolates family a potential candidate for building high thermal stability SPMs.