Coordinative
Reduction of Metal Nodes Enhances the
Hydrolytic Stability of a Paddlewheel Metal–Organic Framework
Dahae Song
Jinhee Bae
Hoon Ji
Min-Bum Kim
Youn-Sang Bae
Kyo Sung Park
Dohyun Moon
Nak Cheon Jeong
10.1021/jacs.9b02114.s001
https://acs.figshare.com/articles/journal_contribution/Coordinative_Reduction_of_Metal_Nodes_Enhances_the_Hydrolytic_Stability_of_a_Paddlewheel_Metal_Organic_Framework/7999055
Enhancement
of hydrolytic stability of metal–organic frameworks
(MOFs) is a challenging issue in MOF chemistry because most MOFs have
shown limitations in their applications under a humid environment.
Meanwhile, inner sphere electron transfer has constituted one of the
most intensively studied subjects in contemporary chemistry. In this
report, we show, for the first time, a new conceptual <i>coordinative
reduction</i> of Cu<sup>2+</sup> ion, which is realized in a
paddlewheel MOF, HKUST-1, with a postsynthetic manner via inner sphere
“single” electron transfer from hydroquinone (H<sub>2</sub>Q) to Cu<sup>2+</sup> through its coordination bond. H<sub>2</sub>Q treatment of HKUST-1 under anhydrous conditions leads to
the single charge (1+) reduction of approximately 30% of Cu<sup>2+</sup> ions. Thus, this coordinative reduction is an excellent reduction
process to be self-controlled in both oxidation state and quantity.
As described below, once Cu<sup>2+</sup> ions are reduced to Cu<sup>+</sup>, the reduction reaction does not proceed further, in terms
of their oxidation state as well as their amount. Also, we demonstrate
that a half of the Cu<sup>+</sup> ions (about 15%) remains in paddlewheel
framework with pseudo square planar geometry and the other half of
the Cu<sup>+</sup> ions (about 15%) forms [Cu(MeCN)<sub>4</sub>]<sup>+</sup> complex in a small cage in the fashion of a ship-in-a-bottle
after dissociation from the framework. Furthermore, we show that the
coordinative reduction results in substantial enhancement of the hydrolytic
stability of HKUST-1 to the extent that its structure remains intact
even after exposure to humid air for two years.
2019-04-05 00:00:00
h 2 Q treatment
coordinative reduction results
framework
sphere electron transfer
Cu
MOF
HKUST
H 2 Q
Metal Nodes Enhances
hydrolytic stability
coordinative reduction
oxidation state