Three-Component Electrochemical Aminoselenation of 1,3-Dienes.

Azoles and organoselenium compounds are pharmacologically important scaffolds in medicinal chemistry and natural products. We developed an efficient regioselective electrochemical aminoselenation reaction of 1,3-dienes, azoles, and diselenide derivatives to access selenium-containing allylazoles skeletons. This protocol is more economical and environmentally friendly and features a broad substrate scope; pyrazole, triazole, and tetrazolium were all tolerated under the standard conditions, which could be applied to the expedient synthesis of bioactive molecules and in the pharmaceutical industry.

Decatungstate-Catalyzed Photochemical Synthesis of Enaminones from Vinyl Azides and Aldehydes.

Visible light-induced synthesis of enaminones from vinyl azides and aldehydes under decatungstate photocatalysis was developed. The reaction proceeds via acyl radical generation from aldehyde, followed by its addition to vinyl azide, nitrogen elimination, hydrogen atom abstraction by the intermediate iminyl radical, and tautomerization. Photochemical synthesis was efficiently conducted under both batch and flow conditions. The method can be applied to various vinyl azides and aldehydes and provides the desired products in 15-72% yields.

Photoredox-Catalyzed Four-Component Reaction for the Synthesis of Complex Secondary Amines.

The one-pot sulfonylation/aminoalkylation of styrene derivatives furnishing substituted γ-sulfonylamines was accomplished through a photoredox-catalyzed four-component reaction. Besides one molecule of water and the sodium counterion of the sulfinate, all atoms of the starting materials are transferred to the final product, rendering this process highly atom-efficient. The operationally simple protocol allows for the simultaneous formation of three new single bonds (C-S, C-N, and C-C) and therefore grants rapid access to structurally diverse products.

Electrochemically Induced Synthesis of Sulfonylated N-Unsubstituted Enamines from Vinyl Azides and Sulfonyl Hydrazides.

Sulfonylated N-unsubstituted enamines were synthesized through a chain of chemical and electrochemical transformations via sulfonylation of vinyl azides. The disclosing of the N-unsubstituted enamines synthesis was based on a unique property of the azido group, which is its ability to eliminate the N2 molecule. Furthermore, a formal paradox is observed: a double bond reacts and a double bond is retained. Electrosynthesis proceeded in an undivided cell equipped with a graphite anode and a stainless steel cathode; NH4I was used as a supporting electrolyte.

Bioactive Natural and Synthetic Peroxides for the Treatment of Helminth and Protozoan Pathogens: Synthesis and Properties.

The significant spread of helminth and protozoan infections, the uncontrolled intake of the known drugs by a large population, the emergence of resistant forms of pathogens have prompted people to search for alternative drugs. In this review, we have focused attention on structures and synthesis of peroxides active against parasites causing neglected tropical diseases and toxoplasmosis. To date, promising active natural, semi-synthetic and synthetic peroxides compounds have been found.

Electrochemically induced oxidative S-O coupling: synthesis of sulfonates from sulfonyl hydrazides and N-hydroxyimides or N-hydroxybenzotriazoles.

The process of oxidative S-O coupling under the action of electric current was developed. Aryl, hetaryl and alkyl sulfonyl hydrazides and N-hydroxy compounds (N-hydroxyimides and N-hydroxybenzotriazoles) are applied as starting reagents for the preparation of sulfonates. The reaction is carried out under constant current conditions in an experimentally convenient undivided electrochemical cell equipped with a graphite anode and a stainless steel cathode under a high current density (60 mA cm-2). NH4Br in this process acts as a supporting electrolyte and participates in the oxidation of the starting compounds to form a coupling product. The developed strategy represents a quite atom-efficient approach: one partner loses two nitrogen and three hydrogen atoms, while another one loses only one hydrogen atom. Cyclic voltammetry and the control experiment allowed us to propose possible reaction pathways: generated through anodic oxidation molecular bromine or its higher oxidation state derivatives oxidize the starting compounds to form reactive species, which couple to form the S-O bond.