An efficient and selective photocatalytic system for the oxidation of sulfides to sulfoxides.

Abstract

isobutene by b-H-elimination: M. G. Klimpel, J. Eppinger, P. Sirsch, W. Scherer, R. Anwander, Organometallics 2002, 21, 4021. [23] E. B. Coughlin, L. M. Henling, J. E. Bercaw, Inorg. Chim. Acta 1996, 242, 205. [24] D. Stern, M. Sabat, T. J. Marks, J. Am. Chem. Soc. 1990, 112, 9558. Ansa-ligand rearrrangement and formation of hydridebridged TMflyover∫dimers seems to have drastic consequences on the catalytic activity in olefin polymerization. For example, the reaction of [{Et2Si(C5H4)(3,4-Me2-C5H2)Lu(m-H)}2] (5) with ethylene, propylene, and 1-hexene gave quantitatively m-hydride/m-alkyl mono-insertion products at ambient temperature. However, similar complexes such as 6 were also shown to be highly efficient in the block copolymerization of ethylene and polar monomers.[3] [25] A comprehensive survey of the 1H NMR chemical shifts (d1⁄4 1.85±8.31 ppm) and 89Y-1H coupling constants (23.8±35.3 Hz) of dimeric yttrium hydrido complexes is presented in: K. C. Hultzsch, P. Voth, K. Beckerle, T. P. Spaniol, J. Okuda, Organometallics 2000, 19, 228. [26] Compound 4a (C52H62O2Si2Y2¥2C6D6) crystallizes from benzene in the monoclinic space group P21/c with a1⁄4 11.7875(2), b1⁄4 14.0396(3), c1⁄4 16.8378(4) a, b1⁄4 104.2053(12)8, V1⁄4 2701.31(10) a3, and 1calcd1⁄4 1.364 gcm 3 for Z1⁄4 2. Data were collected at 193 K on a Nonius Kappa-CCD system. The structure was solved by Patterson methods, and least-square refinement of the model based on 3682 reflections (I> 2.0s(I)) converged to a final R11⁄4 4.0% (wR21⁄4 8.1%). Except H(1), all hydrogen atoms were placed in calculated positions. H(1) was located in difference Fourier maps and refined with isotropic thermal parameters. CCDC-188842 (4a) contains the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/conts/retrieving.html (or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB21EZ, UK; fax: (þ 44)1223-336033; or deposit@ccdc.cam.ac.uk). [27] a) N. Hˆck, W. Oroschin, G. Paolucci, R. D. Fischer, Angew. Chem. 1986, 98, 748; Angew. Chem. Int. Ed. Engl. 1986, 25, 738; b) K. Qiao, R. D. Fischer, G. Paolucci, J. Organomet. Chem. 1993, 456, 185. [28] W. J. Evans, D. K. Drummond, T. P. Hanusa, R. J. Doedens, Organometallics 1987, 6, 2279. [29] W. P. Kretschmer, S. I. Troyanov, A. Meetsma, B. Hessen, J. H. Teuben, Organometallics 1998, 17, 284. [30] a) K. C. Hultzsch, T. P. Spaniol, J. Okuda, Angew. Chem. 1999, 111, 163; Angew. Chem. Int. Ed. 1999, 38, 227; b) S. Arndt, P. Voth, T. P. Spaniol, J. Okuda, Organometallics 2000, 19, 4690. [31] R. Duchateau, C. T. van Wee, A. Meetsma, P. T. van Duijnen, J. H. Teuben, Organometallics 1996, 15, 2279. [32] T. I. Gountchev, T. D. Tilley, Organometallics 1999, 18, 2896. [33] J. P. Mitchell, S. Hajela, S. K. Brookhart, K. I. Hardcastle, L. M. Henling, J. E. Bercaw, J. Am. Chem. Soc. 1996, 118, 1045. Photocatalytic Oxidation