Unsymmetrical Bicentric Organotin Lewis Acids {Me<sub>2</sub>N(CH<sub>2</sub>)<sub>3</sub>}Ph(X)Sn(CH<sub>2</sub>)<sub><i>n</i></sub>SnPh<sub>2</sub>X (X = F, I; <i>n</i> = 1, 3): Syntheses and Structures

The syntheses of the intramolecularly coordinated organotin compounds {Me<sub>2</sub>N­(CH<sub>2</sub>)<sub>3</sub>}­Ph­(X)­SnCH<sub>2</sub>SnPh<sub>2</sub>X (<b>3</b>, X = I; <b>4</b>, X = F) and {Me<sub>2</sub>N­(CH<sub>2</sub>)<sub>3</sub>}­Ph­(F)­Sn­(CH<sub>2</sub>)<sub>3</sub>SnPh<sub>2</sub>F (<b>7</b>) are reported. The compounds have been characterized by elemental analysis, electrospray mass spectrometry, <sup>1</sup>H,<sup>1</sup>H DOSY (<b>4</b>), <sup>13</sup>C, <sup>19</sup>F, and <sup>119</sup>Sn NMR spectroscopy, and single-crystal X-ray diffraction analysis. In the solid state, compound <b>4</b> is a head-to-tail dimer as a result of unsymmetrical Sn–F–Sn bridges, whereas compound <b>7</b> is a monomer with F→Sn intramolecular coordination, giving a six-membered ring. In solution, both <b>4</b> and <b>7</b> are monomeric. The reactions of both <b>4</b> and <b>7</b> with fluoride anion in CD<sub>2</sub>Cl<sub>2</sub> have been investigated by variable-temperature <sup>19</sup>F and <sup>119</sup>Sn NMR spectroscopy.