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after five catalytic cycles, but an appreciable loss of activity was
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in the stereoselective oxidation process was observed. Interest-
ingly, in the case of sulfide 23, a remarkable improvement on the
selectivity was observed.
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Acknowledgments
Authors thank Prof. Marco W. Fraaije for helpful discussion.
A.C. thanks the Principado de Asturias for a predoctoral fellowship.
A.R.-M. (FPU program) thanks the Spanish Ministerio de Ciencia
e Innovación (MICINN) for her predoctoral fellowship which is
financed by the European Social Fund. I.L. acknowledges MICINN
for a research contract under the Ramón y Cajal Program. Finan-
cial support from the Spanish Ministerio de Ciencia e Innovación
(MICINN, Project CTQ2007-61126 and CTQ2010-18330) is grate-
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Appendix A. Supplementary data
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Supplementary data associated with this article can be found, in