| Summary: | The combined use of di-2-pyridyl ketone ((py)<sub>2</sub>CO) with various diols in Mn cluster chemistry has afforded five new compounds, namely, [Mn<sub>11</sub>O<sub>2</sub>(OH)<sub>2</sub>{(py)<sub>2</sub>CO<sub>2</sub>}<sub>5</sub>(pd)(MeCO<sub>2</sub>)<sub>3</sub>(N<sub>3</sub>)<sub>3</sub>(NO<sub>3</sub>)<sub>2</sub>(DMF)<sub>4</sub>](NO<sub>3</sub>)∙2DMF∙H<sub>2</sub>O (<b>1</b>∙2DMF∙H<sub>2</sub>O), [Mn<sub>11</sub>O<sub>2</sub>(OH)<sub>2</sub>{(py)<sub>2</sub>CO<sub>2</sub>}<sub>5</sub>(mpd)(MeCO<sub>2</sub>)<sub>3</sub>(N<sub>3</sub>)<sub>3</sub>(NO<sub>3</sub>)<sub>2</sub>(DMF)<sub>4</sub>](NO<sub>3</sub>) (<b>2</b>), [Mn<sub>12</sub>O<sub>4</sub>(OH)<sub>2</sub>{(py)<sub>2</sub>CO<sub>2</sub>}<sub>4</sub>(mpd)<sub>2</sub>(Me<sub>3</sub>CCO<sub>2</sub>)<sub>4</sub>(NO<sub>3</sub>)<sub>4</sub>(H<sub>2</sub>O)<sub>6</sub>](NO<sub>3</sub>)<sub>2</sub>∙2MeCN (<b>3</b>∙2MeCN), [Mn<sub>4</sub>(OMe)<sub>2</sub>{(py)<sub>2</sub>C(OMe)O}<sub>2</sub>(2-hp)<sub>2</sub>(NO<sub>3</sub>)<sub>2</sub>(DMF)<sub>2</sub>] (<b>4</b>), and [Mn<sub>7</sub>{(py)<sub>2</sub>CO<sub>2</sub>}<sub>4</sub>(2-hp)<sub>4</sub>(NO<sub>3</sub>)<sub>2</sub>(DMF)<sub>2</sub>](ClO<sub>4</sub>)∙DMF (<b>5</b>∙DMF) ((py)<sub>2</sub>CO<sub>2</sub><sup>2−</sup> and (py)<sub>2</sub>C(OMe)O<sup>−</sup> = gem-diol and hemiketal derivatives of di-2-pyridyl ketone, pdH<sub>2</sub> = 1,3-propanediol, mpdH<sub>2</sub> = 2-metly-1,3-propanediol, 2-hpH<sub>2</sub> = 2-(hydroxymethyl)phenol). Complexes <b>1</b> and <b>2</b> are isostructural, possessing an asymmetric [Mn<sup>III</sup><sub>5</sub>Mn<sup>II</sup><sub>6</sub>(μ<sub>4</sub>-O)(μ<sub>3</sub>-O)(μ<sub>3</sub>-OH)(μ-OH)(μ<sub>3</sub>-OR)<sub>2</sub>(μ-OR)<sub>10</sub>(μ-N<sub>3</sub>)]<sup>8+</sup> core. Compound <b>3</b> is based on a multilayer [Mn<sup>III</sup><sub>8</sub>Mn<sup>II</sup><sub>4</sub>(μ<sub>4</sub>-O)<sub>2</sub>(μ<sub>3</sub>-O)<sub>2</sub>(μ<sub>3</sub>-OH)<sub>2</sub>(μ-OR)<sub>12</sub>]<sup>10+</sup> core, while complex <b>4</b> comprises a defective dicubane core. The crystal structure of <b>5</b> reveals that it is based on an unusual non-planar [Mn<sup>III</sup><sub>5</sub>Mn<sup>II</sup><sub>2</sub>(μ-OR)<sub>12</sub>]<sup>7+</sup> core with a serpentine-like topology. Direct current (dc) magnetic susceptibility studies revealed the presence of dominant antiferromagnetic exchange interactions in complex <b>3</b>, while ferromagnetic coupling between the Mn ions was detected in the case of compound <b>5</b>. Fitting of the magnetic data for complex <b>4</b> revealed weak antiferromagnetic interactions along the peripheral Mn<sup>II</sup>∙∙∙Mn<sup>III</sup> ions (<i>J<sub>wb</sub></i> = −0.33 (1) cm<sup>−1</sup>) and ferromagnetic interactions between the central Mn<sup>III</sup>∙∙∙Mn<sup>III</sup> ions (<i>J<sub>bb</sub></i> = 6.28 (1) cm<sup>−1</sup>).
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