Utilization of a Nonemissive Triphosphine Ligand to Construct a Luminescent Gold(I)-Box That Undergoes Mechanochromic Collapse into a Helical Complex
dataset
posted on 2018-04-30, 00:00 authored by Daniel
T. Walters, Reza Babadi Aghakhanpour, Xian B. Powers, Kamran B. Ghiassi, Marilyn M. Olmstead, Alan L. BalchLuminescent
gold(I) complexes ([Au<sub>6</sub>(Triphos)<sub>4</sub>Cl](PF<sub>6</sub>)<sub>5</sub>·2(CH<sub>3</sub>C<sub>6</sub>H<sub>5</sub>), [Au<sub>6</sub>(Triphos)<sub>4</sub>Cl](AsF<sub>6</sub>)<sub>5</sub>·8(CH<sub>3</sub>C<sub>6</sub>H<sub>5</sub>), and
[Au<sub>6</sub>(Triphos)<sub>4</sub>Cl](SbF<sub>6</sub>)<sub>5</sub>·7(CH<sub>3</sub>C<sub>6</sub>H<sub>5</sub>) where Triphos =
bis(2-diphenylphosphinoethyl)phenylphosphine) with a boxlike architecture
have been prepared and crystallographically characterized. A chloride
ion resides at the center of the box with two of the six gold(I) ions
nearby. Mechanical grinding of blue luminescent crystals containing
the cation, [Au<sub>6</sub>(Triphos)<sub>4</sub>Cl]<sup>5+</sup>,
results in their conversion into amorphous solids with green emission
that contain the bridged helicate cation, [μ-Cl{Au<sub>3</sub>(Triphos)<sub>2</sub>}<sub>2</sub>]<sup>5+</sup>. A mechanism of
the mechanochromic transformation is proposed. The structures of the
blue-emitting helicate, [Au<sub>3</sub>(Triphos)<sub>2</sub>](CF<sub>3</sub>SO<sub>3</sub>)<sub>3</sub>·4(CH<sub>3</sub>C<sub>6</sub>H<sub>5</sub>)·H<sub>2</sub>O, and the green-emitting bridged-helicate,
[μ-Cl{Au<sub>3</sub>(Triphos)<sub>2</sub>}<sub>2</sub>](PF<sub>6</sub>)<sub>5</sub>·3CH<sub>3</sub>OH have been determined
by single crystal X-ray diffraction.
