Reversible Sn-Sn Triple Bond Dissociation in a Distannyne: Support for Charge-Shift Bonding Character

摘要

The tin-tin triple bond in the distannyne (ArSnSnAriPr4)-Sn-iPr4, Ar-iPr4 = C6H3-2,6 = (C6H3-2,6-iPr(2))(2), under- goes reversible cleavage in deuterated toluene to afford two :SnAriPr4 radicals in solution as shown by H-1 nuclear magnetic resonance and electron paramagnetic resonance spectroscopy. Variable temperature data afforded an enthalpy of dissociation of Delta H-diss = 17.2 +/- 1.7 kcal mol(-1) via van't Hoff analysis.