Light-driven exchange between extended and contracted lasso-like isomers of a bistable [1]rotaxane

Abstract

The synthesis of a set of benzylic amide [1]rotaxanes via a self-templating clipping approach is described. This methodology supposes the 1 + 1 coupling of isophthaloyl dichloride with an acyclic diamine precursor incorporating a templating arm. The structure of the threaded compounds was determined both in solution and in the solid state. The conversion into the corresponding unthreaded isomers, also obtained by deslipping of [2]rotaxane models, was evaluated in competitive and non-competitive hydrogen-bonding solvents. The switch of the extended and contracted lasso-like isomers of a bistable [1]rotaxane by an olefin isomerization promoted by UV light irradiation was also accomplished and their ring positional integrity was examined.

Photoresponsive Metal-Organic Frameworks as Adjustable Scaffolds in Reticular Chemistry

“…Light has been shown to be an effective stimulus in rotaxanes bearing photoresponsive scaffolds [95][96][97][98]. Thus, interlocked fumaramides are postulated as a useful tool to obtain molecular machines operating through photoisomerization to their equivalent intertwined maleamides (Figure 15) [99][100][101][102].…”

“…Light has been shown to be an effective stimulus in rotaxanes bearing photo sive scaffolds [95][96][97][98]. Thus, interlocked fumaramides are postulated as a usefu obtain molecular machines operating through photoisomerization to their equiv tertwined maleamides (Figure 15) [99][100][101][102]. The incorporation of rotaxanes inside a MOF matrix has turned out to be a strategy to exploit the properties of this type of MIMs in the solid state [103][104][105][106] ing the study of the component's dynamics [107][108][109][110].…”

Copper-Linked Rotaxanes for the Building of Photoresponsive Metal Organic Frameworks with Controlled Cargo Delivery

“…In this work, we describe the building of photoresponsive MOFs using benzylic amide [2]­rotaxanes − as organic linkers and copper­(II) ions as metal nodes. In addition, their behavior in the uptake and release of an small guest was also explored. − In contrast with most of the described coordinating polymers incorporating rotaxanes as linkers, in which the linear interlocked component acts as connector of the metal units, herein we have employed a different approach .…”

Synthesis of an Adamantane-Based Tetralactam and Its Association with Dicarboxamides

“…In one of our research programs focused on the development of novel hydrogen-bonded rotaxanes [9][10][11][12][13][14][15][16], we described the preparation of kinetically stable pseudorotaxanes [12,15] bearing benzylic amide macrocycles and a dicarboxamide-based template such as fumaramides or succinamides. These studies settled the structural requirements of the interlocked systems to allow the dethreading reaction and their kinetic parameters under thermal and photochemical treatments.…”