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Multicomponent reactions represent a powerful method for building complex molecules from structurally simple starting materials. Herein, we report a novel three-component radical-polar crossover reaction involving a tandem addition reaction of two different olefins, which is initiated by the selective addition of fluorosulfonyl radicals to alkyl alkenes. This tandem process provides facile and effective access to multiple functionalized aliphatic sulfonyl fluoride molecules. Further transformation of the products is also demonstrated.

The introduction of sulfonyl fluoride groups into bioactive molecules can often bring about enhanced biological activity, which has attracted more research interest in chemical biology and drug development in recent years. Here, we report the development of a radical fluorosulfonylation of alkenes/intramolecular arylation cascade for the construction of chromanes with sulfonyl fluoride groups attached. The radical 1,2-fluorosulfonyl arylation reactions proceed well in both endo and exo cyclization fashions, allowing for further variation of the distance between the chromane core and the sulfonyl fluoride group.

Recently, radical fluorosulfonylation is emerging as an appealing approach for the synthesis of sulfonyl fluorides, which are highly in demand in various disciplines, particularly in chemical biology and drug discovery. Here, we report the first establishment of radical hydro‐fluorosulfonylation of alkenes, which is enabled by using 1‐fluorosulfonyl 2‐aryl benzoimidazolium (FABI) as an effective redox‐active radical precursor. This method provides a new and facile approach for the synthesis of aliphatic sulfonyl fluorides from unactivated alkenes, and can be further applied to the late‐stage modifications of natural products and peptides, as well as ligation of drugs in combination with click chemistry. Remarkably, this system could enable the radical hydro‐fluorosulfonylation of alkynes, affording valuable alkenylsulfonyl fluoride products with a rare, high Z‐selectivity, which are normally less stable and more challenging to synthesize in comparison with the E‐configured products. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) undergo substantial photochemical losses during their transport from emission sources to receptor sites, resulting in serious implications for their source apportionment and ozone (O 3) formation. Based on the continuous measurements of VOCs in suburban Jinan in August 2022, the effects of photochemical losses on VOC source contributions and O 3 formation were evaluated in this study. The observed and initial concentrations of total VOCs (TVOC) were 12.0 ± 5.1 and 16.0 ± 7.4 ppbv, respectively. Throughout the observation period, alkenes had the most prominent photochemical losses (58.2%), followed by aromatic hydrocarbons (23.1%), accounting for 80.6% and 6.9% of the total losses, respectively. During high O 3 episodes, the photochemical loss of VOCs was 6.9 times higher than that during the cleaning period. Alkene losses (exceeding 67.3%), specifically losses of isoprene, propylene, ethylene, and n-butene, dominated the total losses of VOCs during the O 3 increase period. Eight sources of VOCs were identified by positive matrix factorization (PMF) based on the observed and initial concentration data (OC-PMF and IC-PMF, respectively). Concentrations of all emission sources in the OC-PMF were underestimated by 2.4%–57.1%. Moreover, the contribution of each emission source was over- or underestimated compared with that in case of the IC-PMF. The contributions of biogenic and motor vehicle exhaust emissions were underestimated by 5.3 and 2.8 percentage points, respectively, which was associated with substantial oxidation of the emitted high-reactive species. The contributions of coal/biomass burning and natural gas were overestimated by 2.4 and 3.9 percentage points, respectively, which were related to the emission of low-reactive species (acetylene, ethane, and propane). Based on our results, the photochemical losses of VOCs grossly affect their source apportionment and O 3 formation. Thus, photochemical losses of VOCs must be thoroughly accounted to establish a precise scientific foundation for air-pollution control strategies. [Display omitted] • Photochemical losses contributed 58.2% of initial alkenes and 23.1% of initial aromatics. • Photochemical loss of VOCs during high ozone period was 6.9 times higher than that during cleaning period. • Source apportionment based on measured VOCs might lead to biased conclusions. [ABSTRACT FROM AUTHOR]

Great efforts have been made to develop versatile membranes with carrier-facilitated transport mechanism for olefin/paraffin separation. However, carrier instability has been an overwhelming roadblock, and manufacturing stable membranes have not yet been fulfilled, especially for copper salt-based membranes. Herein, a family of innovative deep eutectic solvents (DESs) were designed by utilizing Brønsted-acidic ammonium salts as hydrogen bond acceptors, which can stabilize CuCl carrier efficaciously. Then, stable copper-decorated deep eutectic solvent based supported liquid membranes (Cu-DESMs) were constructed by confining the as-designed DES and CuCl into porous support for the effective ethylene/ethane separation, where the morphology, molecular interactions and the structure-performance were revealed. The Cu-DESMs exhibited high ethylene permeability of 32.7 Barrer and ethylene/ethane selectivity of 26.8, which far exceeded most of copper salt-based membranes. Particularly, the Cu-DESMs exhibited long-term stability, and the investigation of carrier stability mechanism revealed that deactivation of copper salt-based carriers was included by disproportionation or oxidation reactions, and strong hydrogen-bond interactions and encapsulation effect favored carrier stability. This work offers preliminary guidance for designing stable carrier, and the ultra-stable Cu-DESMs with Brønsted-acidic property will make membrane separation move a step toward practical ethylene/ethane separation. [Display omitted] • Copper-decorated deep eutectic solvent based supported liquid membranes (Cu-DESMs) were constructed to separate ethylene/ethane efficiently. • Brønsted-acidic ammonium salts were used as hydrogen bond acceptor to stabilize CuCl carrier. • Deactivation mechanism of CuCl carrier was revealed and carrier stability strategy was offered. • Strong hydrogen-bond interactions and encapsulation effect favored the carrier stability. • The separation performances of Cu-DESMs could be tailored by the rational molecular design of DESs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mixed protic ionic liquid derived facilitated transport membranes (MPIL-FTMs) were designed for the first time. • Mixed strategy could easily tailor the membrane structure and customize the separation performance. • MPIL-FTMs exhibited robust stability, and the maximum selectivity and permeability reached up to 79.6 and of 561.0 Barrer. • Gas solubility and diffusivity of MPIL-FTMs were evaluated and a fundamental law for mixed strategy was revealed. Mixed strategy has been widely utilized to design novel membranes or tailor membrane structure, however the construction of facilitated transport membranes (FTMs) with mixed strategy has rarely been reported. In this work, eight kinds of mixed protic ionic liquid (MPIL) derived FTMs (MPIL-FTMs) were designed with mixed strategy for highly efficient ethylene/ethane separation by impregnating MPILs and ethylene transport carrier into porous support. The morphology of MPIL-FTMs were characterized by SEM and AFM, and their molecular interactions were investigated by 1H NMR, FTIR and DSC. The MPIL-FTMs exhibited long-term stability and various ethylene permeability-ethylene/ethane selectivity combinations, which indicated mixed strategy could easily customize the separation performances of MPIL-FTMs. Moreover, a fundamental law for mixed strategy was obtained that the two parent PILs with similar chemical structure and molecular interactions favored the synchronous improvement of C 2 H 4 permeability and C 2 H 4 /C 2 H 6 selectivity. For example, the C 2 H 4 permeability of the [BA][Pyr][NO 3 ] derived MPIL-FTM reached up to 561.0 Barrer with improved C 2 H 4 /C 2 H 6 selectivity of 26.7, which were superior to most of reported membranes, thus breaking through the ubiquitous trade-off effect. This study proves the mixed strategy is a promising platform for the design of high-performance FTMs as well as their structure modification, and the marriage of mixed strategy with diversity of ILs creates enormous opportunities to construct advanced membranes for energy-intensive gas separations. [ABSTRACT FROM AUTHOR]

Ethylene/ethane separation is one of the key industrial gas separations which challenges the world because of their similar physical properties. Membrane separation technology holds great promise to replace or combine the currently energy-intensive cryogenic distillation to achieve effective ethylene purification. In this study, a series of double-salt ionic liquid derived facilitated transport membranes (DSIL-FTMs) were designed for the first time aiming at the highly effective ethylene/ethane separation, which were configured by incorporating ethylene transport carrier and double-salt ionic liquids (DSILs) into a robust Nylon support. DSILs are the liquid ionic compositions composing of more than one cation or anion, which offer an opportunity to enhance the design flexibility and structural regulation of the corresponding FTMs. The DSIL-FTMs exhibit good ethylene/ethane separation performance as well as high thermal stability and long-term durability, where the ethylene permeability is about 250 Barrer and ethylene/ethane selectivity reaches up to 67. The spectroscopic characterizations and structure-performance relationship investigation reveal that the excellent separation performances are attributed to the favorable rearrangement of cations and anions in the DSIL-FTMs, where the newly formed ion arrangement and cation-anion interactions of DSIL-FTMs favor the building of the compact membrane structure and obtainment of high carrier activity. This study opens a novel avenue to manipulate the physical-chemical properties of separation membrane by structural diversity of DSILs, and promotes the sustainable prosperity of FTMs for energy-intensive gas molecule separations. [Display omitted] • Double-salt ionic liquid derived facilitated transport membranes (DSIL-FTMs) were designed for the first time. • DSILs enhance the design flexibility and structural regulation of the FTMs. • The DSIL-FTMs exhibit good ethylene/ethane separation performance and durable stability. • The rearrangement of cations and anions in the DSIL-FTMs promotes separation performances. [ABSTRACT FROM AUTHOR]