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In this work, we introduce a novel and general strategy for the environmentally friendly fabrication of mesoporous metal-organic framework (mMOF) thin films via the electrochemically assisted self-assembly (EASA) technique. Implementation of this procedure as a one-step, additive-free, and versatile protocol leads to the in situ simultaneous synthesis and deposition of mesoporous architectures of MOFs at room temperature under green conditions without the need for any base, pretreatment, or chemical modification of the underlying surface. Our procedure provides a controllable method for the synthesis of mMOF thin films (modified electrodes) consisting of hollow three-dimensional hexagonally packed crystals with two-dimensional honeycomb-like mesopores in the walls of the cavities, which grow perpendicularly onto any of the conducting surface. The resulting modified electrodes show enhanced electron transfer properties and better mass transfer performance along with the appropriate signal suitable for electrochemical sensing applications. This work can be a breakthrough and provide a new perspective for the modification and functionalization of the surface with any type of mMOF by the electrochemically driven cooperative (soft-templating) mechanism.

[reaction: see text] It is demonstrated that o-quinones, generated by the electrochemically driven oxidation of the catechols (1a-d) at physiological pH, are rapidly scavenged by 2-mercaptobenzoxazole (3) to give related catecholthioethers (4a-d) via an EC electrochemical mechanism pathway. The electrochemical syntheses of 4a-d have been successfully performed in one-pot in ambient conditions and in an undivided cell using an environmentally friendly method with high atom economy.

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Electrooxidation of 3-substituted catechols has been studied in the presence of dimedone in aqueous solution, using cyclic voltammetry and controlled-potential coulometry. The results indicate that the quinones derived from catechols participate in Michael addition reactions with dimedone to form the corresponding benzofuran derivatives (6a-c). We propose a mechanism for the electrode process. The efficient electrochemical synthesis of 6a-c has been performed at carbon rod electrodes in an undivided cell using a constant current.

Electrochemical oxidation of 3,4-dihydroxybenzoic acid (1) in the presence of 1,3-dimethylbarbituric acid (2) and 1,3-diethyl-2-thiobarbituric acid (3) as nucleophiles in aqueous solution has been studied using cyclic voltammetry and controlled-potential coulometry. The results indicate that 1 via Michael reaction under electro-decarboxylation reaction converts to benzofuro[2,3-d]pyrimidine derivatives (6a, 6b). The electrochemical synthesis of 6a, 6b has been successfully performed in an undivided cell in good yields and purity.

The electrochemical oxidation of catechols was described and has shown that these compounds can be oxidized to related obenzoquinones. The electrochemically generated o-benzoquinones are quite reactive and can be attacked by a variety of nucleophiles under various mechanistic disciplines such as CE, EC, EC ' , ECE, ECEC, ECEC 2 , ECECE, ECECEC, ECECECE and trimerization, in which E represents an electron transfer at the electrode surface, and C represents a homogeneous chemical reaction. The mechanistic pathways and final products are depending on some parameters such as electron withdrawing or donating properties of nucleophile, electrolysis medium (solvent, acidity or pH) and nature of catechol.

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