TY  - JOUR
A1  - Matler, Alexander
A1  - Arrowsmith, Merle
A1  - Schorr, Fabian
A1  - Hermann, Alexander
A1  - Hofmann, Alexander
A1  - Lenczyk, Carsten
A1  - Braunschweig, Holger
T1  - Reactivity of Terminal Iron Borylenes and Bis(borylenes) with Carbodiimides: Cycloaddition, Metathesis, Insertion and C−H Activation Pathways
JF  - European Journal of Inorganic Chemistry
N2  - The reactions of carbodiimides with the iron arylborylene complex [Fe=BDur(CO)\(_{3}\)(PMe\(_{3}\))] (Dur=2,3,5,6-Me\(_{4}\)C\(_{6}\)H) and the iron bis(borylene) complex [Fe{=BDur}{=BN(SiMe\(_{3}\))\(_{2}\)}(CO)\(_{3}\)] yield a wide variety of temperature-dependent products, including known FeBNC and novel FeBNB metallacycles, complexes of N-heterocyclic boracarbene and spiro-boracarbene ligands and a unique 1,3,2,4-diazadiborolyl pianostool complex, characterized by NMR spectroscopy and X-ray crystallography. The product distributions can be rationalized by considering sequences of cycloaddition, metathesis, insertion, and C−H activation pathways mainly governed by sterics.
KW  - structure elucidation
KW  - borylene complexes
KW  - cycloaddition
KW  - metathesis
KW  - reaction mechanisms
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-257397
VL  - 2021
IS  - 45
ER  - 
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  - Heß, Merlin
A1  - Krummenacher, Ivo
A1  - Dellermann, Theresa
A1  - Braunschweig, Holger
T1  - Rhodium-Mediated Stoichiometric Synthesis of Mono-, Bi-, and Bis-1,2-Azaborinines: 1-Rhoda-3,2-azaboroles as Reactive Precursors
JF  - Chemistry—A European Journal
N2  - A series of highly substituted 1,2-azaborinines, including a phenylene-bridged bis-1,2-azaborinine, was synthesized from the reaction of 1,2-azaborete rhodium complexes with variously substituted alkynes. 1-Rhoda-3,2-azaborole complexes, which are accessible by phosphine addition to the corresponding 1,2-azaborete complexes, were also found to be suitable precursors for the synthesis of 1,2-azaborinines and readily reacted with alkynyl-substituted 1,2-azaborinines to generate new regioisomers of bi-1,2-azaborinines, which feature directly connected aromatic rings. Their molecular structures, which can be viewed as boron-nitrogen isosteres of biphenyls, show nearly perpendicular 1,2-azaborinine rings. The new method using rhodacycles instead of 1,2-azaborete complexes as precursors is shown to be more effective, allowing the synthesis of a wider range of 1,2-azaborinines.
KW  - structure elucidation
KW  - azaborinines
KW  - nitrogen heterocycles
KW  - cyclization
KW  - metallacycles
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-256830
VL  - 27
IS  - 37
ER  -