High-yield synthesis of a unique Mn(iii) siloxide complex through KMnO 4 oxidation of a Mn(ii) precursor.

A unique trivalent manganese siloxide complex, blue-violet MnIII Li2 Cl[(Ph2 SiO)2 O]2 (THF)4 ·2THF (3) has been prepared by a straightforward two-step synthetic protocol. Lithiation of (Ph2 SiOH)2 O (1) followed by reaction with MnCl2 (THF)2 gave the structurally remarkable Mn(ii) precursor MnII Li4 Cl2 [(Ph2 SiO)2 O]2 (THF)5 ·2THF (2). Surprisingly, the final oxidation step could be achieved using KMnO4 in THF to provide the Mn(iii) species 3 in high yield (91%). Both title compounds were structurally characterized by single-crystal X-ray diffraction.