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The lecture will give an overview on trifluoromethylation reactions carried out with hypervalent iodine reagents of type 1 and 2 [1]. These transformations, upon which an intact CF3 group may be transferred to a large variety of substrates, are catalyzed or assisted by Br酶nsted and Lewis acids, or by a number of transition-metal complexes. N- and P-trifluoromethylations of benzimidazole or both primary and secondary phosphines, respectively, are used for the preparation of corresponding carbene ligands [2] and novel Pstereogenic phosphines [3] for applications in homogeneous catalysis. Thus, Grubbs-II-type complexes 3 provide high selectivities in e.g. ethenolysis reactions while ligand 4 affords enantioselectivities in the Ir-catalyzed hydrogenation of cyclic iminium salts that are higher than with the parent ligand. Structural modifications [4] and modes of activation of the reagents as well as mechanistic insight deriving from both experiments and quantumchemical calculations [5] will also be presented.

References

[1] For a comprehensive review, see (a) J. Charpentier, N. Fr眉h, A. Togni, Chem. Rev. 2015, 115, 650, and references cited therein.
[2] (a) P.S. Engl, R. Senn, E. Otth, A. Togni, Organometallics 2015, 34, 1384. (b) P.S. Engl, A. Fedorov, C. Cop茅ret, A. Togni, Organometallics 2016, 35, 887.
[3] R. Schwenk, A. Togni, Dalton Trans. 2015, 44, 19566.
[4] V. Matousek, J. Vaklavik, P. Hajek, J. Charpentier, Z.E. Blastik, E. Pietrasiak, A. Budinska, A. Togni, P. Beier, Chem. Eur. J. 2016, 22, 417.
[5] (a) O. Sala, H. P. L眉thi, A. Togni, M. Iannuzzi, J. Hutter, J. Comput. Chem. 2015, 36, 785. (b) O. Sala, N. Santschi, S. Jungen, H.P. L眉thi, M. Iannuzzi, N. Hauser, A. Togni,
Chem. Eur. J. 2016, 22, 1704.