Surprising\nSyntheses of Reduced-Arene Inverse Sandwich\nComplexes of Thorium: (Cp″<sub>2</sub>Th)<sub>2</sub>(<i>μ</i>–<i>η</i><sup>6</sup>:<i>η</i><sup>6</sup>‑C&lt

In efforts to generate [Cp″<sub>3</sub>Th<sup>III</sup>Me]<sup>1–</sup> [Cp″ = C<sub>5</sub>H<sub>3</sub>(SiMe<sub>3</sub>)<sub>2</sub>] from potassium graphite (KC<sub>8</sub>) and\nCp″<sub>3</sub>Th<sup>IV</sup>Me in the presence of benzene\nand 18-crown-6 or 2.2.2-cryptand, the dark red reduced benzene inverse\nsandwich complex (Cp″<sub>2</sub>Th)<sub>2</sub>(<i>μ</i>–<i>η</i><sup>6</sup>:η<sup>6</sup>-C<sub>6</sub>H<sub>6</sub>), <b>1</b>, was unexpectedly isolated\nand crystallographically characterized. Surprisingly, <b>1</b> can also be synthesized by the addition of MeLi to Cp″<sub>3</sub>Th<sup>III</sup> in the presence of benzene and a chelate\neven though Cp″<sub>3</sub>Th<sup>III</sup> and (Cp″<sub>3</sub>Th<sup>II</sup>)<sup>1–</sup> are stable in the presence\nof arenes. The crystal structure of <b>1</b> reveals a twisted\nboat with distortion from planarity of the bridging C<sub>6</sub> moiety\nwith torsion angles of 9.37(4), 10.10(8), and −19.02(4)°.\nComplex <b>1</b> exhibits an axial EPR signal at 77 K with <i>g</i><sub>||</sub> = 1.97 and <i>g</i><sub>⊥</sub> = 1.89, characteristic of a Th(III) 6d<sup>1</sup> ion, and a magnetic\nmoment of 2.54 μ<sub>B</sub> at 298 K. When toluene is present\nduring the reduction of Cp″<sub>3</sub>Th<sup>IV</sup>Me with\nKC<sub>8</sub>, a dark maroon solution is generated that has physical\nand spectroscopic properties consistent with the formation of the\nanalogous reduced toluene complex (Cp″<sub>2</sub>Th)<sub>2</sub>(<i>μ–η</i><sup>6</sup><i>:η</i><sup>6</sup>-C<sub>7</sub>H<sub>8</sub>), <b>2</b>. Complex <b>2</b> can also be made by the addition of MeLi to Cp″<sub>3</sub>Th<sup>III</sup> in the presence of toluene and a chelate.