Glycerol as a promoting medium for cross-coupling reactions of diaryl diselenides with vinyl bromides

Role of Group 12 Metals in the Reduction of H2O2 by Santi's Reagent: A Computational Mechanistic Investigation

PhSeZnCl, which is also known as Santi's reagent, can catalyze the reduction of hydrogen peroxide by thiols with a GPx-like mechanism. In this work, the first step of this catalytic cycle, i.e., the reduction of H2O2 by PhSeZnCl, is investigated in silico using state-of-the-art density functional theory calculations. Then, the role of the metal is evaluated by replacing Zn with its group 12 siblings (Cd and Hg). The thermodynamic and kinetic factors favoring Zn are elucidated. Furthermore, the role of the halogen is considered by replacing Cl with Br in all three metal compounds, and this turns out to be negligible. Finally, the overall GPx-like mechanism of PhSeZnCl and PhSeZnBr is discussed by evaluating the energetics of the mechanistic path leading to the disulfide product.

ChemoselectiveN-tert-butyloxycarbonylation of amines in glycerol

The operational simplicity, cleaner reaction, rapid reaction convergence, functional group tolerance, excellent yield, high selectivity, catalyst-free feature and solvent recyclability are the distinct advantages of this protocol. This makes the protocol feasible, economical and environmentally benign.

Sonochemistry: An efficient alternative to the synthesis of 3-selanylindoles using CuI as catalyst

Ultrasonic (US) irradiation was successfully used as an alternative energy source to prepare 3-selanylindoles through the direct selanylation of indoles with diorganyl diselenides using CuI (20 mol%) as catalyst and DMSO as the solvent. By using this US-promoted reaction, eleven 3-organylselanylindoles were prepared selectively and in good yields. A comparative study between the reactions under conventional heating, microwave and ultrasound irradiations was performed, and it was observed advantage in using US over the other heating systems.

Stereoselective synthesis of alkyl styryl selenides in one-pot: a straightforward approach by in situ dialkyl diselenide formation under transition metal-free conditions

One-pot synthesis of alkyl styryl selenides using KSeCN as selenium source.

Glycerol as an efficient medium for the petasis borono-mannich reaction

The multicomponent Petasis borono–Mannich (PBM) reaction is a useful tool for the preparation of complex molecules in a single step from boronic acids, aldehydes/ketones, and amines. Here, we describe the use of glycerol in the PBM reaction of salicylaldehydes or 2-pyridinecarbaldehyde with several boronic acids and secondary amines. From these readily available starting materials, alkylaminophenols, 2-substituted pyridines, and 2H-chromenes were prepared in reasonable to good yields. Glycerol was compared with other solvents, and in some cases, it provided the reaction product in higher yield. Crude glycerol, as generated by the biodiesel industry, was evaluated and found to be a suitable solvent for the PBM reaction, successfully expanding the potential use of this industry by-product. Based on density functional theory (DFT) calculations and the obtained experimental results, the involvement of glycerol-derived boronic esters in the reaction mechanism is suggested to be competitive with the free boronic acid pathway. Similar Gibbs free energies for the aryl migration from the boronate species to the iminium were determined for both mechanisms.

Glycerol as suitable solvent for the synthesis of metallic species and catalysis

This Minireview considers the foremost reported works involving glycerol as a solvent in the synthesis of organometallic complexes and metallic nanoparticles. This analysis highlights their catalytic applications. A special emphasis is devoted to the ability of glycerol to immobilize nanometric species, which, in turn, enables an efficient recycling of the catalytic phase to give metal-free organic products.

Glycerol − glycerol triacetate mixtures as green reaction mediums

Three representative organic reactions were performed in various glycerol−triacetin mixtures to tune the polarity of the reaction mixture and thus to increase both the solubility of reactants and the product yields. In all reactions, it was found that reaction performance was affected by the glycerol to triacetin ratio as the solubility of the substrates in the solvent determined product yield. Thereby, employing optimal glycerol to triacetin ratio will result in maximum product yield.

“The green side of the moon: ecofriendly aspects of organoselenium chemistry”

Key aspects for the development of a greener synthesis and the use of the organoselenium compounds.