An extended series of Mn-based cage-like phenylsilsesquioxanes were obtained via convenient self-assembly reactions and complexations with 1,10-phenanthroline. The structural features of these cage complexes such as (i) various nuclearities and types of silsesquioxane ligands, (ii) encapsulations of hydroxide and chloride species, and (iii) spontaneous oxidations of MnII to MnIII are established by single-crystal X-ray diffraction, including the use of synchrotron radiation. One of the synthesized compounds represents a unique feature among metallacomplexes - the presence of three metal ions with different oxidation states (NaI, MnII, and MnIII). Furthermore, the first-ever evaluation of Mn-silsesquioxanes as precatalysts in oxidative amidation (OA) reactions allowed us to develop a very effective protocol of OA of alcohols and aldehydes with low loading of Mn (5 mol% and 2.5 mol%, respectively).
Bibliographical noteFunding Information:
This work was financially supported by the Russian Science Foundation (project no. 22-13-00250). Elemental analysis data were collected using the equipment of the Center for Molecular Composition Studies of INEOS RAS with the support from the Ministry of Science and Higher Education of the Russian Federation. D. G. acknowledges the RUDN University Scientific Projects Grant System, project no. 025239-2-174, Israel Science Foundation (ISF) grant no. 370/20 and the Esther K. and M. Mark Watkins Chair for Synthetic Organic Chemistry. XANES experiment was supported by the Ministry of Education of the Russian Federation: No. 075-15-2022-1107.
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