A [Mn<sub>8</sub>] Defective Supertetrahedron T3 and\nIts Dimeric [Mn<sub>16</sub>] Analogue

The initial use of 2-(pyridin-2-yl)propane-1,3-diol (pypdH<sub>2</sub>) in Mn cluster chemistry has afforded two new mixed-valence\npolynuclear Mn clusters, namely, [Mn<sub>8</sub>Ο<sub>5</sub>(pypd)(hmp)<sub>3</sub>(O<sub>2</sub>CCMe<sub>3</sub>)<sub>8</sub>] (<b>1</b>) and [Mn<sub>16</sub>Ο<sub>10</sub>(N<sub>3</sub>)<sub>2</sub>(pypd)<sub>2</sub>{(py)<sub>2</sub>CO<sub>2</sub>}<sub>4</sub>(O<sub>2</sub>CEt)<sub>12</sub>] (<b>2</b>) (hmp<sup>–</sup> = deprotonated 2-hydroxymethylpyridine; (py)<sub>2</sub>CO<sub>2</sub><sup>2–</sup> = deprotonated gem-diol form of\ndi-2-pyridyl ketone). Compound <b>1</b> features a novel [Mn<sup>III</sup><sub>7</sub>Mn<sup>II</sup>(μ<sub>4</sub>-O)<sub>2</sub>(μ<sub>3</sub>-O)<sub>3</sub>(μ-OR)<sub>5</sub>]<sup>8+</sup> structural core resembling a supertetrahedron T3, lacking\ntwo apexes, while complex <b>2</b> has a [Mn<sup>III</sup><sub>14</sub>Mn<sup>II</sup><sub>2</sub>(μ<sub>4</sub>-O)<sub>4</sub>(μ<sub>3</sub>-O)<sub>6</sub>(μ-N<sub>3</sub>)<sub>2</sub>(μ<sub>3</sub>-OR)<sub>2</sub>(μ-OR)<sub>8</sub>]<sup>14+</sup> core consisting of two [Mn<sub>8</sub>] subunits related\nto <b>1</b> and thus is a dimeric analogue of <b>1</b>. Direct current (dc) magnetic susceptibility studies revealed the\npresence of dominant antiferromagentic exchange interactions between\nthe Mn ions in complexes <b>1</b> and <b>2</b> and small\nground state spin values for both compounds. Overall, this work highlights\nthe capability of polyol-like chelates like pypdH<sub>2</sub> to stabilize\nhigh nuclearity 3d metal clusters based on polynuclear building blocks.