TY  - JOUR
A1  - Ivanova, Svetlana
A1  - Köster, Eva
A1  - Holstein, Julian J.
A1  - Keller, Niklas
A1  - Clever, Guido H.
A1  - Bein, Thomas
A1  - Beuerle, Florian
T1  - Isoreticular crystallization of highly porous cubic covalent organic cage compounds
JF  - Angewandte Chemie International Edition
N2  - Modular frameworks featuring well-defined pore structures in microscale domains establish tailor-made porous materials. For open molecular solids however, maintaining long-range order after desolvation is inherently challenging, since packing is usually governed by only a few supramolecular interactions. Here we report on two series of nanocubes obtained by co-condensation of two different hexahydroxy tribenzotriquinacenes (TBTQs) and benzene-1,4-diboronic acids (BDBAs) with varying linear alkyl chains in 2,5-position. n-Butyl groups at the apical position of the TBTQ vertices yielded soluble model compounds, which were analyzed by mass spectrometry and NMR spectroscopy. In contrast, methyl-substituted cages spontaneously crystallized as isostructural and highly porous solids with BET surface areas and pore volumes of up to 3426 m\(^2\) g\(^{-1}\) and 1.84 cm\(^3\) g\(^{-1}\). Single crystal X-ray diffraction and sorption measurements revealed an intricate cubic arrangement of alternating micro- and mesopores in the range of 0.97–2.2 nm that are fine-tuned by the alkyl substituents at the BDBA linker.
KW  - organic chemistry
KW  - structure elucidation
KW  - boronateesters
KW  - cage compounds
KW  - dynamic covalent chemistry
KW  - porousmaterials
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-256462
VL  - 60
IS  - 32
ER  - 
TY  - JOUR
A1  - Li, Ru-Jin
A1  - Han, Muxin
A1  - Tessarolo, Jacopo
A1  - Holstein, Julian J.
A1  - Lübben, Jens
A1  - Dittrich, Birger
A1  - Volkmann, Christian
A1  - Finze, Maik
A1  - Jenne, Carsten
A1  - Clever, Guido H.
T1  - Successive Photoswitching and Derivatization Effects in Photochromic Dithienylethene-Based Coordination Cages
JF  - ChemPhotoChem
N2  - A new series of [Pd2(L)4] cages based on photochromic dithienylethene (DTE) ligands allowed us to gain insight into the successive photoswitching of multiple DTE moieties in a confined metallo-supramolecular assembly. Three new X-ray structures of [Pd2(o-L4)4], [Pd2(o-L1)2(c-L1)2] and [Pd2(c-L1)4] (o-L and c-L = open and closed forms of DTE ligands, respectively) were obtained. The structures deliver snapshots of three different combinations of DTE photoisomeric states within the cage, facilitating a comparison of the all-open with the all-closed, and most notably, an intermediate form where open and closed switches co-exist in the same cage. Moreover, a series of spherical anionic borate clusters was introduced in order to study their roles in the light-controllable host–guest chemistry. The binding guests show higher affinities with the flexible open cage [Pd2(o-L1)4] than with the rigid closed cage [Pd2(c-L1)4]. For the [B12F12]2− guest, thermodynamic data obtained from NMR experiments was compared to results from isothermal titration calorimetry (ITC).
KW  - coordination cages
KW  - dithienylethene
KW  - host-guest systems
KW  - photoswitches
KW  - supramolecular chemistry
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236815
VL  - 3
ER  -