title: Construction of crystalline 2D covalent organic frameworks with remarkable chemical (acid/base) stability via a combined reversible and irreversible route.
abstract: Two new chemically stable [acid and base] 2D crystalline covalent organic frameworks (COFs) (TpPa-1 and TpPa-2) were synthesized using combined reversible and irreversible organic reactions. Syntheses of these COFs were done by the Schiff base reactions of 1,3,5-triformylphloroglucinol (Tp) with p-phenylenediamine (Pa-1) and 2,5-dimethyl-p-phenylenediamine (Pa-2), respectively, in 1:1 mesitylene/dioxane. The expected enol-imine (OH) form underwent irreversible proton tautomerism, and only the keto-enamine form was observed. Because of the irreversible nature of the total reaction and the absence of an imine bond in the system, TpPa-1 and TpPa-2 showed strong resistance toward acid (9 N HCl) and boiling water. Moreover, TpPa-2 showed exceptional stability in base (9 N NaOH) as well.
authors.affiliation: Physical/Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India.
authors.forename: Sharath
authors.initials: S
authors.lastname: Kandambeth
authors.forename: Arijit
authors.initials: A
authors.lastname: Mallick
authors.forename: Binit
authors.initials: B
authors.lastname: Lukose
authors.forename: Manoj V
authors.initials: MV
authors.lastname: Mane
authors.forename: Thomas
authors.initials: T
authors.lastname: Heine
authors.forename: Rahul
authors.initials: R
authors.lastname: Banerjee