Design and synthesis of new electrophilic reagents based on sulfur
Final Report Abstract
Our work illustrates the potential of imidazolium sulfuranes to become reference platforms for the development of new reagents able to promote the umpolung of synthetically useful organic groups. In this regard they might be interesting alternatives to hypervalent I(III) reagents. Ongoing studies in our laboratory are aimed to demonstrate the generality of the concept, and to further evaluate the synthetic utility of new reagents that might be able to promote electrophilic aminations, trifluoromethylations, arylatons or vinylations. In this regard, it must be mentioned that we have only evaluated the metal-free reactivity of salts 8, 9, 18 and 20. To us, it seems obvious that the rich chemistry of these compounds can be further expanded by the use of typical organometallic catalyst; for example, in the area of C-H activation. Moreover, the synthetic potential of the imidazolium sulfuranes in transformations proceeding via radical mechanisms has never been explored; thus, we envisaged interesting applications for our compounds in emerging areas such as of photocatalysis or electrosynthesis. Ongoing research in our group is aimed to demonstrate the generality of the concepts herein presented, and to further evaluate the synthetic utility of the new reagents prepared in metal catalyzed processes.
Publications
- "Alkynylthioimidazolium Salts: Efficient Reagents for the Synthesis of Alkynyl Sulfides by Electrophilic Thioalkynylation." Chem. Eur. J. 2017, 23, 75-78
J. Peña, G. Talavera, B. Waldecker, M. Alcarazo
(See online at https://doi.org/10.1002/chem.201604760) - "Regio- and Stereoselective Chlorocyanation of Alkynes." Angew. Chem. Int. Ed. 2017, 56, 13401-13405
A. G. Barrado, A. Zieliński, R. Goddard, M. Alcarazo
(See online at https://doi.org/10.1002/anie.201705851) - "Two‐Step Synthesis of Unsymmetrical Diaryl Sulfides by Electrophilic Thiolation of Non‐functionalized (Hetero)arenes." Chem. Eur. J. 2018, 24, 15026-15035
M. J. Böhm, C. Golz, I. Rüter, M. Alcarazo
(See online at https://doi.org/10.1002/chem.201802806) - "Synthesis of Alkynylthiopyridinium Salts and Their Use as Thioketene Equivalents." Chem. Eur. J. 2019, 25, 10472-10477
K. F. G. Averesch, H. Pesch, C. Golz, M. Alcarazo
(See online at https://doi.org/10.1002/chem.201901895)