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Separation of acetylene (C2H2) from carbon dioxide (CO2) or ethylene (C2H4) 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, MB12H12(dpb)2 (termed as BSF‐3 and BSF‐3‐Co for M=Cu and Co), for highly selective capture of C2H2. The high C2H2 capacity and remarkable C2H2/CO2 selectivity resulted from the unique anionic boron cluster functionality as well as the suitable pore size with cooperative proton‐hydride dihydrogen bonding sites (B−Hδ−⋅⋅⋅Hδ+−C≡C−Hδ+⋅⋅⋅Hδ−−B). This new type of C2H2‐specific functional sites represents a fresh paradigm distinct from those in previous leading materials based on open metal sites, strong electrostatics, or hydrogen bonding. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis and application of icosahedral boron cluster compounds has been studied extensively since their discovery several decades ago; however, two aspects of their chemistry have received little attention: The possibility to form inorganic/organic fused boraheterocycles and their potential to act as antimicrobial agents. This work comprises the preparation of a class of 3D diborabenzoxazole analogues with the closo‐dodecaborate in place of the benzene moiety. The presented synthetic procedures provide access to a wide range of diboraheterocycles under mild conditions. These 3D heterocycles exhibit strong and selective antimicrobial activity against Neisseria gonorrhoeae, a widespread bacterial pathogen that has shown increasing incidences of multidrug resistance and for which the development of new antimicrobial compounds is urgently needed. [ABSTRACT FROM AUTHOR]

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 [B12H12]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. [ABSTRACT FROM AUTHOR]

The synthesis and structural characterization of new derivatives of [B12H12]2− is of fundamental interest and is expected to allow for extended applications. Herein we report on the synthesis of a series of amidine, amide, urea and isocyanate derivatives based on the amino-closo-dodecaborate anion [B12H11NH3]−. Their structures have been confirmed by spectroscopic methods, and nine crystal structures are presented. [ABSTRACT FROM AUTHOR]

[Display omitted] • Remarkable C 2 H 2 /C 2 H 4 selectivity and high C 2 H 2 capacity in BSF-9 with reasonable illustration of the C 2 H 2 and C 2 H 4 adsorption difference by modeling study. • Excellent dynamic separation performance of C 2 H 2 /C 2 H 4 in BSF-9 with good recyclability. • High CO 2 /N 2 selectivity achieved both by BSF-4 and BSF-9 through near-sieving effect. • Inverse ambient adsorption capacity of C 3 H 8 and C 2 H 6 observed in BSF-9. • Distinct C 3 H 8 adsorption kinetics observed for BSF-4 and BSF-9. Two isostructural closo -dodecaborate [B 12 H 12 ]2- pillared metal organic frameworks (MOFs), BSF-4 and BSF-9, were synthesized and compared in the performance of selective gas adsorption and separation. BSF-9 with symmetrical interpenetration and two contracted 1D channel exhibited efficient uptake of C 2 H 2 (85.1/76.3 mLg−1, 278/298 K) with high separation selectivity over C 2 H 4 (41.4, 298 K), outperforming BSF-4 (7.3, 298 K) and many benchmark MOFs. The selectivity of C 2 H 6 /CH 4 , CO 2 /CH 4 , CO 2 /N 2 on BSF-9 (25.2, 9.9, 56.6) and BSF-4 (19.0, 8.9, 41.7) was all relatively high and comparable. The practical gas separation ability for C 2 H 2 /C 2 H 4 mixtures on BSF-9 was confirmed by mixed gas breakthrough experiments with negligible capacity loss after 4 cycles, indicating its potential for purification of ethylene from acetylene-containing industrial gas mixtures. The C 2 H 2 and C 2 H 4 bonding sites and bonding energies within the framework of BSF-9 were further compared by density functional theory (DFT) study, indicating that C 2 H 2 can be trapped tightly between two anionic [B 12 H 12 ]2- by four synergistic dihydrogen bonds while C 2 H 4 only interacts with single [B 12 H 12 ]2- with weaker bonding energy. BSF-4 with asymmetrical interpenetration and single extended 1D channel showed higher selectivity of C 3 H 8 /CH 4 (138.5, 298 K) than that of BSF-9 (64.0, 298 K). Inverse ambient adsorption capacity of C 3 H 8 < C 2 H 6 was observed in BSF-9 due to the small pore window and 1D channel. [ABSTRACT FROM AUTHOR]

A closo -dodecaborate [B 12 H 12 ]2- functionalized metal organic framework (MOF), BSF-3, constructed by the self-assembly of the Cu(II) cation, 1,4-di(pyridin-4-yl)benzene linker and cluster [B 12 H 12 ]2- pillar was investigated for the adsorption separation of light hydrocarbons. The activated MOF exhibited efficient uptake of CO 2 and C2–C3 hydrocarbons with high separation selectivity of C 3 H 8 (138), C 2 H 2 (205), C 2 H 4 (23), C 2 H 6 (13) and CO 2 (9) over CH 4 , outperforming many popular MOFs. The practical gas separation ability for C 2 H 2 /CH 4 , CO 2 /CH 4 and C 3 H 8 /C 2 H 6 /CH 4 was confirmed by mixed gas breakthrough experiments with no capacity loss after 7 cycles, indicating its potential for purification of methane from natural gas and pyrolysis gas. The gas bonding sites within the framework were further studied by modelling studies, which indicated that the anionic [B 12 H 12 ]2- pillar contributed the most to capturing hydrocarbon molecules by multiple B-Hδ-···Hδ+-C interactions. Microporous dodecaborate hybrid metal organic supramolecuar frameworks were synthesized for the separation of methane from CO 2 and C2–C3 hydrocarbons. Enhanced separation performance was observed with reticular pore expansion, as demonstrated by static gas adsorption, modelling study and dynamic breakthrough experiments. [Display omitted] • High C2–C3 hydrocarbons and CO 2 uptake as well as high adsorption selectivity over CH 4 were achieved. • Practical separation of C 2 H 2 /CH 4 , CO 2 /CH 4 and C 3 H 8 /C 2 H 6 /CH 4 mixtures were confirmed by mixed gas breakthrough experiments. • Constant performance over 7 cycles of adsorption/desorption breakthrough experiments was obtained. [ABSTRACT FROM AUTHOR]