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Two kinds of indium-based MOF materials (In-MOF 1 and In-MOF 2) were synthesized using a solvothermal method using two different pyridine carboxylic acid ligands. Single crystal X-ray diffraction shows that In-MOF 1 is a three-dimensional frame containing four connected [In(CO2)4] units and nine connected [In3(μ3-O)(CO2)6N3] units, while In-MOF 2 is a three-dimensional structure with eight connected [In(CO2)3(CO)N] units. Moreover, the adsorption and separation properties of the MOFs for C2H2, CO2 and CH4 were investigated systematically in order to study the regulation of porosity by the subtle changes in the structure of organic linkers. The results show that both kinds of MOFs have certain gas adsorption and separation capacity, which is mainly determined by the structure, function and adjustable porosity. This work not only reports two MOFs with the potential to separate C2H2/CH4, CO2/CH4 and C2H2/CO2, but also provides valuable guidance for the design and synthesis of porous MOFs with better performance in the future. [ABSTRACT FROM AUTHOR]

Rhodium-catalyzed regio- and stereoselective three-component carboamidation of 1,3-enynes has been realized using indoles and dioxazolones as the functionalizing reagents. A wide range of multi-substituted skipped 1,4-dienes have been constructed in good yields and excellent stereoselectivity. The stereoselectivity is under substrate control. 1,3-Enynes bearing a relatively bulky alkyne terminus reacted with Z-selectivity. In contrast, a sterically less hindered alkyne terminus tends to predominantly give the E-configured skipped diene. [ABSTRACT FROM AUTHOR]

Chiral RhIII catalysts can catalyze the asymmetric [4+1] spiroannulation of O-pivaloyl oximes with α-diazo homophthalimides under redox-neutral and acid/base-neutral conditions, leading to formation of chiral spirocyclic imines as a result of C–H activation and N–O cleavage. The reaction proceeded with high efficiency and features broad substrate scope, mild reaction conditions, and high to excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

Rhodium(III)-catalyzed C–C coupling of heteroarenes and fluorinated α-diazo diketones has been realized for the facile synthesis of 3-arylchromones. The reaction proceeds via chelation-assisted C–H activation, carbene insertion, and uncatalyzed intramolecular nucleophilic aromatic substitution, with C–F cleavage being accommodated in the nucleophilic aromatic substitution step. Three classes of heteroarenes have been defined with decent functional group tolerance. [ABSTRACT FROM AUTHOR]

Rhodium(III)-catalyzed mild and oxidative [4+1] spiroannulation has been realized via C–H activation of oximes and benzoic acids with 1-diazonaphthelen-2(1H)-ones as coupling reagents. This transformation integrates C–H activation and dearomatization and provides a direct approach to spirocyclic isoindole N-oxides and isobenzofuranones with functional group tolerance. [ABSTRACT FROM AUTHOR]

Efficient synthesis of 2-naphthols was realized by Ru(ii)-catalyzed C–H activation of aryl nitrones and intermolecular [3+3] annulation with α-diazo sulfonyl ketones under redox-neutral conditions. Easily available α-diazo sulfonyl ketones act as a three-carbon component in the reaction. [ABSTRACT FROM AUTHOR]

Rhodium(iii)-catalyzed mild benzylic α-fluoroalkenylation of 8-methylquinolines with gem-difluorostyrenes has been developed. This reaction occurred via C–H activation and C–F cleavage and is applicable to a wide range of substrates, leading to the synthesis of Z-alkenyl fluorides under mild and redox-neutral conditions with high regio- and stereoselectivity. [ABSTRACT FROM AUTHOR]

Rhodium-catalyzed enantioselective C-H alkynylation of achiral and racemic sulfoxides is disclosed with alkynyl bromide as the alkynylating reagent. A wide range of chiral sulfoxides have been constructed in good yield and excellent enantioselectivity (up to 99% ee, s -factor up to > 500) via desymmetrization, kinetic resolution, and parallel kinetic resolution under mild reaction conditions. The high enantioselectivity was rendered by the chiral cyclopentadienyl rhodium(iii) catalyst paired with a chiral carboxamide additive. The interactions between the chiral catalyst, the sulfoxide, and the chiral carboxylic amide during the C-H bond cleavage offer the asymmetric induction, which is validated by DFT calculations. The chiral carboxamide functions as a base to promote C-H activation and offers an additional chiral environment during the C-H cleavage., Competing Interests: The authors declare no competing financial interests., (This journal is © The Royal Society of Chemistry.)