Exploring the dynamics of Zr-based metal–organic frameworks containing mechanically interlocked molecular shuttles

Abstract

Zr(IV) metal-organic frameworks (MOFs) UiO-68 and PCN-57, containing linkers triphenylene dicarboxylate (TPDC) and tetramethyl-triphenylene dicarboxylate (TTDC), respectively, were doped with an H shaped, tetracarboxylate linker that contains a [2]rotaxane molecular...

Integrating the Mechanical Bond into Metal-Organic Frameworks

“…31 The ability to switch on and off the translational motion of the bulk macrocycle in the pore via an external stimulus may allow the MIM to act as a molecular gate in the MOF similar to that achieved using [2]rotaxane molecular valves in porous silica. 41 The resulting modulation of the rate of guest diffusion could be similarly exploited for drug delivery applications. 41 A MIM linker can also be used to join individual lattices using mechanical bonds by attaching metal coordinating groups to both the axle and wheel components using the same designs (direct strut, side group, crossbar) as employed for MOF linkers with rotation and translational dynamics (Figures 4A-4C).…”

“…41 The resulting modulation of the rate of guest diffusion could be similarly exploited for drug delivery applications. 41 A MIM linker can also be used to join individual lattices using mechanical bonds by attaching metal coordinating groups to both the axle and wheel components using the same designs (direct strut, side group, crossbar) as employed for MOF linkers with rotation and translational dynamics (Figures 4A-4C). This has the potential to create new MOF topologies with woven lattices and materials in which the mechanical bond is more of a structural component and less of a decorative one.…”

Impact of the proximity effect on uranyl coordination of conformationally variable weakly-bonded cucurbit[6]uril-bipyridinium pseudorotaxane

“…Among all the available organic linkers, pseudorotaxanes have been demonstrated to be versatile precursors which can endow the prepared materials with unique topologies 17,18 and molecular dynamics. 19–21 In a typical pseudorotaxane, the macrocyclic host and the string guest bond with each other through weak interactions between these two components. This provides an important platform for designing new organic ligands through non-covalent binding, which can produce richer variations in the linkers than direct chemical modification.…”

Applying reticular synthesis to the design of Cu-based MOFs with mechanically interlocked linkers

“…The term "robust dynamics" was coined by Stoddart and Yaghi to describe incorporating mechanically interlocked molecules (MIMs) into metal-organic frameworks (MOFs) [9]. Although a few examples of MIMs in MOFs [10][11][12][13][14][15][16][17][18] have been reported, to reliably create a material exhibiting robust dynamics, some degree of predictability in design is desirable. Reticular synthesis-the process of assembling judiciously designed rigid molecular building blocks into predetermined ordered structures-seems ideal for this purpose [19].…”

“…MOF materials in the UWDM (University of Windsor Dynamic Material) series have provided significant progress towards achieving the goal of robust dynamics but have fallen short of providing rational design parameters [10][11][12][14][15][16][17]. In the case of UWDM-1 (Fig.…”