Polyethylene glycol-400/H₃PO₂: an eco-friendly reductive system for the synthesis of selanylesters

Abstract

An alternative green method was described for the synthesis of selanylesters by reactions of acyl chlorides with arylselenols, generated in situ by reaction of diaryl diselenides with hypophosphorous acid (H3PO2) using polyethylene glycol-400 (PEG-400) as the solvent.

Synthetic Approaches to Selenoesters

“…Finally, it is important to highlight the work of Alves, [32] who presented a new methodology for the synthesis of selenoesters without the need to use metals. In this case, the generation of the nucleophilic species of selenium occurred through the reaction between diselenides and hypophosphorous acid (H 3 PO 2 ), in PEG‐400, for 30 minutes.…”

“…Finally,i ti si mportant to highlight the work of Alves, [32] who presented an ew methodology for the synthesis of selenoesters withoutthe need to use metals.I nthis case, the generation of the nucleophilic species of selenium occurredt hrough the reactionb etween diselenidesa nd hypophosphorous acid (H 3 PO 2 ), in PEG-400, for 30 minutes. As described by Günther, [33] there is evidencet hat the reaction betweenH 2 PO 3 ,w ater and diselenides leads to the formation of selenol and H 3 PO 3 .…”

Water-Dependent Selective Synthesis of Mono- or Bis-Selanyl Alkenes from Terminal Alkynes

“…While the organylselenol is generated in situ under nitrogen atmosphere, the bad smell of this selenating agent does not become an inconvenient. In recent years, our group published four methodologies using H 3 PO 2 to the generation of organylselenols in situ from diorganyl diselenides, with application in the synthesis of unsymmetrical diaryl selenides,organylselanyl pyridines, benzoselenazoles or benzoselenazolinesand selanylesters …”

Rongalite®/PEG-400 as reducing system in the synthesis of new glycerol-derived selenol esters using anhydrides and bis-(2,2-dimethyl-1,3-dioxolanylmethyl)diselenide as substrates

“…36 Generally, these methods have limitations related to metal-catalyzed synthesis, 37 high temperatures and volatile solvents 29 and long reaction times. 32 However, new methods have been described to meet the principles of green chemistry, for instance, by using alternative and recyclable solvents, 25,38 microwave irradiation, 39 solvent-free and metal-free conditions. 27 In recent years, the importance of sustainable chemistry for the preparation of chalcogen-containing compounds (S, Se and Te) has increased.…”

“…[11][12][13][14] They were also used as a precursors in the synthesis of vinyl compounds, 15 in the formation of C-peptide bonds, [16][17][18] and the synthesis of some natural occurring compounds, [19][20][21][22][23] besides having proven antioxidant properties. 24 Various methods have been described for the synthesis of selenol esters, for example, by the condensation of selenolate anions 25 or radicals 26 with carbonyl compounds, such as aldehydes, 27,28 anhydrides 26,29-34 acyl chlorides [29][30][31][32][33][34] or starting from chalcogen acetylenes 35 and aryl iodides. 36 Generally, these methods have limitations related to metal-catalyzed synthesis, 37 high temperatures and volatile solvents 29 and long reaction times.…”