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Dopamine surface chemistry has been of great interest because of its universal coating property and ability to transform nonadhesive molecules into adhesive molecules. Catechol oxidation and intramolecular cyclization underlie the unique property of dopamine (DA) surface chemistry and provide clues for developing new surface modification reagents such as norepinephrine, 5-pyrogallol-2-aminoethane, and perfluorinated DA derivatives. Based on these inspiring properties, a fast and universal surface chemistry technique using 4-(3-aminopropyl)-benzene-1,2-diol (3-catecholpropanamine, CPA) is reported herein. A single carbon insertion in the aliphatic chain of DA gives rise to the significantly accelerated intermolecular assembly and surface coating of CPA. The effect of CPA conjugation on an anticoagulant polysaccharide coating is also investigated. The use of CPA instead of DA to make polysaccharide coating materials improves the coating rate, while maintaining excellent antiplatelet performance on the coated surface.

Mussel-inspired surface chemistry, in which catechol derivatives play an important role, has garnered extensive research interest owing to material-independent surface coating capability and easy implementation to a wide range of applications. Generally, sequential reactions comprising catechol oxidation, intramolecular reaction of oxidized catechols with nucleophiles, and intermolecular assembly result in polymers that can adhere to many diverse surfaces. Although amines and thiols have similar reactivity toward oxidized catechols, most studies have been conducted with catechol and amine groups as essentials. Surface coating with catechol-thiol has not been investigated. In this study, we show that 4-(2-mercapto-ethyl)-benzene-1,2-diol (catechol-thiol) can serve as a surface coating agent in the presence of a strong oxidant. A wide range of materials are coated with catechol-thiol, and an additional grafting of the functional molecules onto the surface is also performed through well-established thiol chemistry, Michael addition, and thiol-ene reaction.

The position of identical functional groups and the subsequent electron density of structural benzene rings in a zinc-based metal–organic framework (MOF) have been controlled to reveal flexibility (or breathing behavior) differences. Both ortho- and para-positioned bi-functional benzene-1,4-dicarboxylic acid (BDC) ligands were synthesized with amino-, chloro-, methoxy-, and nitro groups. Additionally, two tri-functionalized, dimethoxy-amino and dimethoxy-nitro BDCs were prepared. All bi- and tri-functionalized BDCs were successfully incorporated into DABCO MOFs (DMOFs), except two diamino BDCs which were insoluble and thermally unstable. Among the eight bi-/tri-functionalized DMOFs, only para-dimethoxy exhibited flexibility in its framework after evacuation in preparation for N2 isotherm measurement. Since the dimethoxy combination has the most electron-rich environment in the benzene ring of the BDC in this series, this indicates that electron density plays a role in the flexibility changes of identically bi-functionalized DMOFs. However, the electron density alone could not fully explain the flexibility changes suggesting that the position of the functional groups is also important. These findings have been corroborated through the synthesis of two tri-functionalized DMOFs with identical functional group locations but opposite electronic environments.

Silver carbonate (Ag2CO3), a common transition metal-based inorganic carbonate, is widely utilized in palladium-catalyzed C–H activations as an oxidant in the redox cycle. Silver carbonate can also act as an external base in the reaction medium, especially in organic solvents with acidic protons. Its superior alkynophilicity and basicity make silver carbonate an ideal catalyst for organic reactions with alkynes, carboxylic acids, and related compounds. This review describes recent reports of silver carbonate-catalyzed and silver carbonate-mediated organic transformations, including cyclizations, cross-couplings, and decarboxylations.