Phosphine oxides are successfully used as building blocks, specifically, for the synthesis of substituted vitamin D₃ analogs. Tertiary phosphine oxides are key targets in the chemistry of organophosphorus compounds. They are widely used as ligands for metal complex catalysts, special solvents for stabilization of nanosystems in the synthesis of semiconductors, extractants for noble, rare-earth, and transuranium elements, fire-retardants, and photochromic and lumines-cent materials.^1-4

Of particular interest are functionalized tertiary phosphine oxides; however, their synthesis involves some difficulties. A convenient synthetic approach to such compounds is based on the addition of secondary phosphine oxides to functionally substituted alkynes at high temperature by using equivalent amounts of oxidant and catalyst.^1-4

In our work the synthesis of different (di)phenilphosphine oxide derivatives in electrocatalytic conditions have been performed. Our approach provides an efficient way to construct different phosphorus-containing products, including bisphosphonates, benzo[b]phosphole oxides, alkynyl(diaryl)phosphine oxides with high yield at room temperature in oxidant-free media. The mechanism includes forming cobalt and silver complexes with diphenylphosphine oxide, their electrochemical reduction/oxidation leads to binding with acetylene and obtaining target products.

Acknowledgements

This work was supported by the Russian Science Foundation no. 14-23-00016.

References

1 Wang, T.; Chen,S.; Shao, A.; Gao, M.; Huang, Y.; Lei, A. Org.Lett. 2015, 17, 118.

2 Chen, Y.-R.; Duan, W.-L. J. Am. Chem. Soc. 2013, 135, 16754.

3 Dvorko, M. Yu.; Glotova, T. E.; Ushakov, I. A.; Gusarova, N. K. Russ. J. Org. Chem. 2010, 45, 485.

4 Srinivas, V.; Balaraman, E.; Sajna, K.V.; Kumara Swamy, K.C. Eur. J. Org. Chem.

2011, 4222–4230.