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Propyne/propylene (C 3 H 4 /C 3 H 6 ) separation is an important but challenging industrial process to produce polymer-grade C 3 H 6 and recover high-purity C 3 H 4 . Herein, we report an ultrastable TiF 6 2- anion cross-linked metal-organic framework (ZNU-2) with precisely controlled pore size, shape and functionality for benchmark C 3 H 4 storage (3.9/7.7 mmol g -1 at 0.01/1.0 bar and 298 K) and record high C 3 H 4 /C 3 H 6 (10/90) separation potential (31.0 mol kg -1 ). The remarkable C 3 H 4 /C 3 H 6 (1/99, 10/90, 50/50) separation performance was fully demonstrated by simulated and experimental breakthroughs under various conditions with excellent recyclability and high productivity (42 mol kg -1 ) of polymer-grade C 3 H 6 from a 1/99 C 3 H 4 /C 3 H 6 mixture. A modelling study revealed that the symmetrical spatial distribution of six TiF 6 2- on the icosahedral cage surface provides two distinct binding sites for C 3 H 4 adsorption: one serves as a tailored single C 3 H 4 molecule trap and the other boosts C 3 H 4 accommodation by cooperative host-guest and guest-guest interactions., (© 2022 Wiley-VCH GmbH.)

Separation of acetylene (C 2 H 2 ) from carbon dioxide (CO 2 ) or ethylene (C 2 H 4 ) is important in industry but limited by the low capacity and selectivity owing to their similar molecular sizes and physical properties. Herein, we report two novel dodecaborate-hybrid metal-organic frameworks, MB 12 H 12 (dpb) 2 (termed as BSF-3 and BSF-3-Co for M=Cu and Co), for highly selective capture of C 2 H 2 . The high C 2 H 2 capacity and remarkable C 2 H 2 /CO 2 selectivity resulted from the unique anionic boron cluster functionality as well as the suitable pore size with cooperative proton-hydride dihydrogen bonding sites (B-H δ- ⋅⋅⋅H δ+ -C≡C-H δ+ ⋅⋅⋅H δ- -B). This new type of C 2 H 2 -specific functional sites represents a fresh paradigm distinct from those in previous leading materials based on open metal sites, strong electrostatics, or hydrogen bonding., (© 2020 Wiley-VCH GmbH.)

The lithiacarborane [Li-CB 11 H 11 ] - plays a central role in carborane chemistry, as it is a key intermediate to achieve the selective functionalization of the monocarba-closo-dodecaborate [CB 11 H 12 ] - for applications in various fields. Also, it is an organometallic species of fundamental interest because it represents a 3D analogue of phenyllithium featuring an exo C-Li bond in addition to the delocalized negative endo charge of the spherical cluster. For the first time, the elusive and highly reactive endo/exo formal dianion [CB 11 H 11 ] 2- has been isolated as its lithiate as well as zincate in pure form and fully characterized. DFT calculations corroborate the experimental findings and underscore the remarkably high reactivity of the lithiacarborane. Subsequent derivatizations demonstrate the relevance of its initial clean formation., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A novel 3D metal-organic framework BSF-1 based on the closo-dodecaborate cluster [B 12 H 12 ] 2- was readily prepared at room temperature by supramolecular assembly of CuB 12 H 12 and 1,2-bis(4-pyridyl)acetylene. The permanent microporous structure was studied by X-ray crystallography, powder X-ray diffraction, IR spectroscopy, thermogravimetric analysis, and gas sorption. The experimental and theoretical study of the gas sorption behavior of BSF-1 for N 2 , C 2 H 2 , C 2 H 4 , CO 2 , C 3 H 8 , C 2 H 6 , and CH 4 indicated excellent separation selectivities for C 3 H 8 /CH 4 , C 2 H 6 /CH 4 , and C 2 H 2 /CH 4 as well as moderately high separation selectivities for C 2 H 2 /C 2 H 4 , C 2 H 2 /CO 2 , and CO 2 /CH 4 . Moreover, the practical separation performance of C 3 H 8 /CH 4 and C 2 H 6 /CH 4 was confirmed by dynamic breakthrough experiments. The good cyclability and high water/thermal stability render it suitable for real industrial applications., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

1,2,3-Trisubstituted closo-dodecaborates with B-O, B-N, and B-C bonds as well as a fused borane oxazole ring have been synthesized by rhodium-catalyzed direct cage B-H alkenylation and annulation of ureido boranes in the first reported example of regioselective B-H bond functionalization of the [B 12 H 12 ] 2- cage by transition-metal catalysis. This reaction proceeded at room temperature under ambient conditions and exhibited excellent selectivity for efficient monoalkenylation with good functional-group tolerance. The urea moiety enabled B-H activation by acting as a directing group, was incorporated in the oxazole ring in situ, and also avoided multiple alkenylation. A possible mechanism is proposed on the basis of the isolation of a rhodium agostic intermediate and control experiments., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The asymmetric synthesis of ent-ketorfanol from simple and commercially available precursors is reported. A Rh(I) -catalyzed intramolecular CH alkenylation/torquoselective 6π electrocyclization cascade provides a fused bicyclic 1,2-dihydropyridine as a key intermediate. Computational studies were performed to understand the high torquoselectivity of the key 6π electrocyclization. The computational results demonstrate that a conformational effect is responsible for the observed selectivity. The ketone functionality and final ring are introduced in a single step by a redox-neutral acid-catalyzed rearrangement of a vicinal diol to give the requisite carbonyl, followed by intramolecular Friedel-Crafts alkylation., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The first example of C alkylation of 1,2-dihydropyridines with alkyl triflates and Michael acceptors was developed to introduce quaternary carbon centers with high regio- and diastereoselectivity. Hydride or carbon nucleophile addition to the resultant iminium ion also proceeded with high diastereoselectivity. Carbon nucleophile addition results in an unprecedented level of substitution to provide piperidine rings with adjacent tetrasubstituted carbon atoms., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Sly silyl caught in the act: Protonation of a mesitylene ring by the strongly acidic arenium carborane [CH(3)C(6)H(6)]- [CHB(11)Me(5)Br(6)] initiates a cascade reaction that results in a stable beta-silyl allyl cation (see picture, H yellow, C blue, silyl allyl group red). Remarkably, the driving force in the reaction suffices to disrupt a stable aromatic ring in favor of a cationic reactive intermediate.