Network Diversity through Decoration of Trigonal‐Prismatic Nodes: Two‐Step Crystal Engineering of Cationic Metal–Organic Materials

Abstract

In einem zweistufigen Prozess wurden zuerst trigonal‐prismatische molekulare Primärbausteine [Cr3O(isonic)6]+ (tp‐PMBB‐1) aufgebaut, die dann durch lineare Brücken oder quadratisch‐planare Knoten zu drei neuartigen, hoch geladenen kationischen Metall‐organischen Materialien (MOMs) mit snx‐, snw‐ und stp‐Topologie verknüpft wurden.

The asc Trinodal Platform: Two‐Step Assembly of Triangular, Tetrahedral, and Trigonal‐Prismatic Molecular Building Blocks

“…MBBs most typically consist of metal carboxylate or metal pyridine clusters where the peripheral points of extension dictate the respective geometrical building units, corresponding to a vertex figure that can be reduced to a single vertex. We address these handicaps herein by applying our recently reported two-step crystal engineering strategy [18] to generate the first trinodal MOM platform.The two-step approach relies upon first preparing a trigonal-prismatic primary molecular building block (tp-PMBB) based on [Cr 3 (m 3 -O)(CO 2 ) 6 ] clusters decorated with six coordinating ligands (Figure 1). These high-symmetry nets are typically finetuned through the organic linker(s) and have spawned the concept of isoreticular chemistry.…”

“…These high-symmetry nets are typically finetuned through the organic linker(s) and have spawned the concept of isoreticular chemistry. [18] Herein, we describe how tp-PMBB-1 can be reacted with tetrahedral (Zn 2+ , Cd 2+ ) and three triangular MBBs (1,3,5-benzenetricarboxylic acid, H 3 btc; 1,3,5-tris(4-carboxyphenyl) benzene, H 3 btb; 4,4',4''-[1,3,5-benzenetriyltris(carbonylimino)] trisbenzoic acid, H 3 btctb) in N,N-dimethylformamide (DMF; see the Supporting Information for further details) to afford the first four examples of trinodal networks involving triangular, tetrahedral, and trigonal-prismatic building blocks.The prototypal compound, tp-PMBB-1-asc-1, is based upon trigonal-prismatic clusters [Cr 3 O(isonic) 6 (H 2 O) 3 ] + (isonic = pyridine-4-carboxylate) coordinated to six tetrahedral Zn 2+ cations that are in turn coordinated to two triangular btc 3À anions. [15] However, only a handful of these nets might be described as platforms for which the underlying topology can serve as a blueprint for the generation of families of related materials through judicious selection of the MBBs, as exemplified by uninodal 6-c pcu (IRMOFs) [11a] and binodal 3,24-c rht [16] platforms.…”

“…We believe that this is largely related to the difficulties associated with controlling the stoichiometry and order of self-assembly of three or more different MBBs in a one-pot reaction. We address these handicaps herein by applying our recently reported two-step crystal engineering strategy [18] to generate the first trinodal MOM platform.The two-step approach relies upon first preparing a trigonal-prismatic primary molecular building block (tp-PMBB) based on [Cr 3 (m 3 -O)(CO 2 ) 6 ] clusters decorated with six coordinating ligands (Figure 1). [19] The hexapyridyl variant, tp-PMBB-1, is soluble, cheap, and robust and can subsequently be used for the preparation of binodal nets.…”

“…[19] The hexapyridyl variant, tp-PMBB-1, is soluble, cheap, and robust and can subsequently be used for the preparation of binodal nets. [18] Herein, we describe how tp-PMBB-1 can be reacted with tetrahedral (Zn 2+ , Cd 2+ ) and three triangular MBBs (1,3,5-benzenetricarboxylic acid, H 3 btc; 1,3,5-tris(4-carboxyphenyl) benzene, H 3 btb; 4,4',4''-[1,3,5-benzenetriyltris(carbonylimino)] trisbenzoic acid, H 3 btctb) in N,N-dimethylformamide (DMF; see the Supporting Information for further details) to afford the first four examples of trinodal networks involving triangular, tetrahedral, and trigonal-prismatic building blocks.The prototypal compound, tp-PMBB-1-asc-1, is based upon trigonal-prismatic clusters [Cr 3 O(isonic) 6 (H 2 O) 3 ] + (isonic = pyridine-4-carboxylate) coordinated to six tetrahedral Zn 2+ cations that are in turn coordinated to two triangular btc 3À anions. The resulting tetrahedral MBB, Zn(CO 2 ) 2 (py) 2 , is well known for its role in sustaining hydrogen-bonded [20] and diamondoid networks.…”

“…We believe that this is largely related to the difficulties associated with controlling the stoichiometry and order of self-assembly of three or more different MBBs in a one-pot reaction. We address these handicaps herein by applying our recently reported two-step crystal engineering strategy [18] to generate the first trinodal MOM platform.…”