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A new gold(i) self-relay catalysis consisting of a 3,3-rearrangement, Nazarov cyclization and Michael addition cascade of 1,3-enyne acetates with aurones and their derived azadienes is reported, producing functionalized cyclopentenones.

Exercise and cold exposure are two stimuli that have been suggested as solely effective to modulate adipose tissue metabolism and improve metabolic health in obese populations. The two primary organs involved in energy metabolism during exercise and/or cold exposure are skeletal muscle and adipose tissue. Adipose tissue can be divided mainly into two types: white adipose tissue (WAT), which primarily stores energy, and brown adipose tissue (BAT), known as the primary source of thermogenesis. The exercise-stimulated release of myokines allows for crosstalk between skeletal muscle and adipose tissue, partially mediating the beneficial effects of exercise. Cold exposure is another trigger for the regulation of myokine secretions, thus increasing adipose tissue metabolism, especially via activation of BAT. Therefore, this has generated the hypothesis that exercise in conjunction with cold exposure might be the optimal regimen to regulate myokine profiles and gain more beneficial health effects. However, to date, human experimental data regarding different exercise (frequency, type, time and intensity) and cold exposure (temperature, time and frequency) patterns are scarce. In this review, we will summarize the current human clinical trials investigating the regulation of myokines induced by exercise combined with cold exposure, to elaborate on the roles of myokines in mediating adipose tissue metabolism.

A new Lewis acid-catalyzed [2 + 2] cycloaddition/retroelectrocyclization (CA-RE)/1,6-addition relay of aurone-derived 1-azadienes and 1-alkynylnaphthalen-2-ols has been reported, leading to the regio- and diastereoselective synthesis of 1,2-dihydrobenzofuro[3,2-b]pyridine with a chiral carbon center and an axial chirality in good yields. This protocol enables the C-C double-bond scission/recombination to rapidly construct aza-heterocyclic architectures and features 100% atom utilization, a wide substrate scope, good compatibility with substituents, and excellent diastereoselectivity.

Tunable electrocatalytic annulation reactions of o-arylalkynylanilines have been established, leading to green and divergent syntheses of skeletally diverse indoles by adjusting the electrolytes and the solvents. The presence of ammonium halides as the electrolytes enabled the halogenation of o-arylalkynylanilines to give C3-halogenated indoles whereas naphtho[1',2':4,5]furo[3,2-b]indoles could be obtained by changing the electrolyte from ammonium halides to KI. Interestingly, by combining acetone as the solvent and both NH4I and NH4Cl as the electrolytes, the reaction worked through an intramolecular annulation and [5 + 1] cyclization cascade to form naphtho[1',2':5,6][1,3]oxazino[3,4-a]indoles.

A new photocatalytic three-component annulation of 2-alkynylaryldiazonium tetrafluoroborates with γ-hydroxyl terminal alkynes and sodium metabisulfite is reported using fac-Ir(ppy)3 as the photocatalyst for the first time and used to produce a series of (Z)-thiochromene 1,1-dioxides bearing an exocyclic double bond with moderate to good yields in a highly stereoselective manner. A wide variety of easily available substrates with substituent diversity could successfully participate in this photocatalysis with good functional group tolerance.

A new chelation-controlled hydrofuranization of unactivated olefins with α-alkynyl arylols is reported for the first time, and used to produce a wide range of C3-alkylated benzofurans with generally good yields under mild conditions. A bidentate directing group is used to suppress β-hydride elimination and in turn facilitate a protodepalladation event. In addition to 100% atom utilization, good functional group tolerance and mild conditions, the present catalysis did not demand any additional ligand, additives and bases/acids, making the transformation simple and facile and it thus opens new avenues for catalytic difunctionalization of alkynes and olefins.

Photoinduced arene–alkyne [3 + 2] cycloaddition cascades of 1-alkynylnaphthalen-2-ols without a photosensitizer were developed for the first time, enabling tunable synthesis of skeletally diverse bridged hexacyclic architectures with good yields and complete stereoselectivities through solvent-dependent divergent dearomatized cyclodimerizations. The photocatalysis in N,N-dimethylformamide (DMF) delivered functionalized bicyclo[3.2.1]octane-containing bridged oxa-heterocycles, whereas tetrahydrofuran (THF) oriented high stereoselectivity to offer bridged carbocycles. The reaction pathway generates two classes of complex three-dimensional structures that evolve from the same planar internal alkynes.

A new copper-catalyzed radical-triggered fluoromethylation-spirotricyclization of enediyne- and enyne-nitrile-containing para-quinone methides (p-QMs) was reported for the first time, and used to produce a series of hitherto unreported cyclohexadienone-based pentacyclic spiroindenes with moderate to good yields and complete regioselectivity. The reaction proceeds through a complex difluoromethyl or trifluoromethyl radical-induced 1,6-addition/5-exo-dig, 6-exo-dig, 6-endo-trig tricyclization/single electron transfer (SET) process, resulting in the direct formation of up to three new rings and four chemical bonds in one step. The present Cu-catalyzed strategy accommodates a good substrate scope and is distinguished by its high bond-forming efficiency, annulation efficiency, and high regioselectivity.

The combination of Pd(TFA)2 and an N,N′-disulfonyl bisimidazoline ligand shows high catalytic activity and excellent asymmetric induction in the addition of arylboronic acids to cyclic N-sulfonyl k...

Two classes of new catalytic spiroannulation-fluormethylfunctionaliztions of para-quinone methide (p-QM)-containing 1,5-enynes have been established under redox-neutral conditions. Palladium-catalyzed spiroannulation-iododifluoromethylation with ethyl difluoroiodoacetate oriented completely stereoselective access to (Z)-spiroindenes and the latter included copper-catalyzed three-component spiroannulation-cyanotrifluoromethylation starting from Togni's reagent and trimethylsilanecarbonitrile (TMSCN). Both reaction pathways involve fluoroalkyl radical-triggered 1,6-addition/5-exo-dig annulation/metal radical cross-coupling/reductive elimination sequence, providing practical and stereoselective protocols for rapidly constructing cyclohexadienone-containing spiroindenes with generally good yields.

A new electrochemical three-component annulation-iodosulfonylation of 1,5-enyne-containing para-quinone methides (p-QMs) has been established by using available arylsulfonyl hydrazides and potassium iodide under environmentally benign conditions. The electrosynthesis offers sustainable and efficient access to construct spirocyclohexadienone-containing (E)-indenes without any additional catalyst or oxidant through a sulfonyl-radical-triggered 1,6-addition and an I+-mediated ipso-cyclization cascade. Notably, potassium iodide plays the triple role of an electrolyte, a redox catalyst, as well as an iodination reagent.

A new Lewis acid catalyzed alkyne–carbonyl metathesis/oxa-Michael addition relay was first reported, leading to the atom-economic synthesis of unreported functionalized indolone-containing naphtho[...

In recent years, para-quinone methides (p-QMs) have emerged as attractive and versatile synthons in organic synthesis owing to their high reactivity. Consequently, p-QM chemistry has attracted increasing attention and remarkable advances have been achieved. Among the numerous transformations involving p-QMs, catalytic reactions play a pivotal role, and a variety of catalytic systems mediated by Lewis acids, Bronsted acids, bases, transition metals, N-heterocyclic carbenes, and other catalysts have been established for performing 1,6-conjugate addition reactions. Various molecular scaffolds have been constructed using p-QMs to obtain the core structures of numerous natural and synthetic substances of chemical and biomedical relevance. In this review, we provide a comprehensive overview of recent progress in this rapidly growing field by summarizing the 1,6-conjugate addition and annulation reactions of p-QMs with consideration of their mechanisms and applications.

A new photoinduced photocatalyst-free energy-transfer strategy for double [2 + 2] cycloaddition relay of yne–allenones is reported for the first time and used to produce a series of hitherto unreported hexacyclic 1-naphthols with good yields and complete diastereoselectivity. The reaction pathway generates a class of complex three-dimensional structures with two all-carbon quaternary centers evolved from the planar conjugated system through cleavage and recombination of the C–C triple bond of yne–allenones, enabling the direct formation of four new rings in one step.

Selenium nanoparticles have attracted extensive attention due to their good bioavailability and activity. In the present study, a new form of selenium nanoparticle (Low molecular weight chitosan selenium nanoparticles (LCS-SeNPs)) were synthesized in a system of sodium selenite and acetic acid. The size, element state, morphology and elementary composition of LCS-SeNPs were characterized by using various spectroscopic and microscopic measurements. The protection of LCS-SeNPs against dextran sulfate sodium (DSS)-induced intestinal barrier dysfunction and the inherent mechanisms of this process were investigated. The results showed that LCS-SeNPs, with an average diameter of 198 nm, zero-valent and orange-red relatively uniform spherical particles were prepared. LCS-SeNPs were mainly composed of C, N, O and Se elements, of which Se accounted for 39.03% of the four elements C, N, O and Se. LCS-SeNPs reduced colon injury and inflammation symptoms and improved intestinal barrier dysfunction. LCS-SeNPs significantly reduced serum and colonic inflammatory cytokines TNF-α and IL-6 levels. Moreover, LCS-SeNPs remarkably increased antioxidant enzyme GSH-Px levels in serum and colonic tissue. Further studies on inflammatory pathways showed that LCS-SeNPs alleviated DSS-induced colitis through the NF-κB signaling pathway, and relieved inflammatory associated oxidative stress through the Nrf2 signaling pathway. Our findings suggested that LCS-SeNPs are a promising selenium species with potential applications in the treatment of oxidative stress related inflammatory intestinal diseases.

A concise copper catalysis strategy for the addition-cyclization of cyclic oxime esters across 1,6-enynes with high stereoselectivity to generate 1-indanones bearing an all-carbon quaternary center is reported. In this process, single-electron reduction of cyclic oxime esters enables deconstructive carbon-carbon cleavage to provide a key cyanopropyl radical poised for the addition-cyclization. This reaction is redox-neutral, exhibits good functional group compatibility, and features 100% atomic utilization. This process driven by copper catalyst makes readily available cyclic oxime esters as bifunctional reagents to demonstrate convergent synthesis.

A silver-catalyzed nitration/annulation of α-alkynyl arylols is reported by using tert-butyl nitrite (TBN) as a NO2 radical precursor, from which a set of 3-nitrated benzofurans were synthesized with moderate to good yields. This transformation initiated by an in situ generated NO2 radical proceeds efficiently under mild and neutral redox conditions, which provides a new pathway toward the 3-nitrobenzofuran framework via catalytic difunctionalization of internal alkynes.

A double-base copromoted 1,4-oxo-migration/cyclization cascade of β-alkynyl ketones was reported, enabling to form a range of functionalized 1-indanones with moderate to good yields and high diastereoselectivity in the presence of t-BuOK as a Bronsted base and N,N'-dimethylethanediamine (DMEDA) as a Lewis base. Some of these 1-indanones were successfully transformed into 2-haloethyl benzoates with one all-carbon quaternary stereocenter by 1,2-dichloroethane (DCE) or 1,2-dibromoethane (DBE) as both a reactant and a reaction media. This method also features high atomic utilization (100%), high diastereoselectivity, and mild reaction conditions.

Two types of new oxidant-free radical multicomponent reactions of β-alkynyl ketones, aryldiazonium salts, and DABCO·(SO2)2 (DABSO) were established, leading to the tunable generation of two class o...

A new double annulation cascade involving a [2 + 2] cycloaddition–retroelectrocyclization (CA–RE) process was first reported, leading to the generation of unprecedented dibenzoannulated naphtho[2,1...

The determination of favorable areas for shale gas enrichment under a syncline background is an important problem that needs to be addressed. The research objects in this study are typical shale gas blocks of the southern Sichuan Basin and the Xiuwu Basin in the Yangtze region with Lower Cambrian and Upper Ordovician–Lower Silurian shales. We carried out permeability tests parallel and perpendicular to the bedding surface, permeability tests with different overburden pressures, and permeability tests and isothermal adsorption experiments under different osmotic pressures before and after the adsorption of methane parallel to the bedding surface. In addition, along with the analysis of drilling data statistics, the enrichment of marine shale gas under a syncline background was studied with respect to dip angle and burial depth. The results show that the preservation conditions of shale gas are better when the dip angle is below 10°, while they are relatively poorer at angle more than 20°. This is due to the migration of natural gas, mainly in parallel direction to the bedding surface, leading to favorable shale gas preservation with decreasing angle. Based on double effects of the overburden pressure and gas adsorption (both increase) parallel to the bedding surface on the permeability of shale, the permeability decreases. When the overburden pressure increases to 10–15 MPa, the permeability parallel to the shale layer changes suddenly and decreases to a low value, which means that under the syncline background, the drilling depth with good shale gas production capacity should be at least 1019–1529 m.

A Cu-catalyzed [4+1] annulation of N-aryl-1,2,3,4-tetrahydroisoquinolines (N-aryl THIQs) with α-diazoketones has been established under oxidative conditions, leading to the construction of a series of indolo[2,1-a]isoquinolines with generally good yields. The reaction enables dediazotized dicarbonylation of α-diazoketones, creating direct C(sp3 )/C(sp2 )-H bond bifunctionalization to access tetracyclic aza-heterocyclic skeletons.

Shale gas as an unconventional gas has made a significant impact on worldwide energy supply. The heterogeneity of the shale reservoir has a dramatic effect on the shale gas accumulation. The heterogeneity characterization of the Paleozoic Wufeng-Longmaxi Formation Shale in the Upper Yangtze Region is studied within a sequence stratigraphic framework by testing in situ gas content, organic matter, minerals, porosity, permeability, and the observation and description of core and thin sections, and data statistics. Results show that the shelf depocenter has higher porosity than the shelf margin and the permeability is obviously lower at the transitional zone compared to neighboring areas. The most obvious characteristic of organic matter and mineral composition is that the TOC and quartz content at the lower section of the formation deposited during transgressive systems tract is higher than that at the upper section of the formation deposited during highstand systems tract throughout the whole deposition zone. The laminae are primarily developed at the upper section of the formation. The natural fracture is mainly developed at the Qiyueshan fault zone and the Xuefeng Mountain fault zone. The primary controlling factors of shale gas accumulation are organic matter and porosity. The transgressive systems tracts with high organic matter content and porosity at the lower section of the formation are more favorable for gas accumulation. The shale gas resources and exploration potential are mainly concentrated in the shelf depocenter.

A new palladium(II)-catalyzed cyclization-radical addition cascade enables the direct construction of 1,3-dimethylene-substituted isobenzofuran derivatives containing a vinyl aryl sulfone unit in good yields by treating with β-alkynyl ketones, aryl diazonium salts, and DABCO·(SO2)2. The oxidant-free multicomponent reaction features good substrate scope and functional group tolerance, which proceeds through a sequence of Heck coupling, oxo-cyclization, and SO2 insertion.

Two types of new synergistic silver/scandium catalytic spiroketalizations of β-alkynyl ketones have been achieved, delivering a variety of skeletally diverse spirocyclic isochromenes in generally good yields and good diastereoselectivity in an atom economical manner. In the former, bimetallic catalytic [4 + 2] cycloaddition worked well to provide a series of 6,6-benzannulated spiroketals, whereas the latter gave unprecedented nitrogen-containing 5,6-benzannulated spiroketals through catalytic [3 + 2] cycloaddition under mild conditions.

Two new types of silver-catalyzed nitration–annulations of 2-alkynylanilines with tert-butyl nitrite (TBN) were reported, leading to the selective formation of a variety of nitrated indoles and indazole-2-oxides by changing the N-protection of 2-alkynylanilines. Ag-Catalyzed nitration–annulation of N-sulfonyl 2-alkynylanilines without C4 substituents afforded 5-nitroindoles under neutral-redox conditions, whereas the presence of C5 substituents gave 7-nitroindoles through silver catalysis. N-Methyl 2-alkynylanilines underwent a completely different process to furnish aroyl indazole-2-oxides.

A new single Pd-catalyzed decarboxylative allylation-nucleophilic cyclization relay is reported by using α-alkynyl arylols and vinylethylene carbonates (or vinyl carbamates), and a wide range of 3-allyl benzofurans with generally good yields were stereoselectively synthesized under mild conditions, among which the complete stereoselectivity of some cases was also observed. Notably, the present catalysts can tolerate air conditions without any ligand, additive, or base, opening new avenues to build up oxa-heterocycle frameworks through catalytic difunctionalization of internal alkynes.

Permeability stress-sensitivity is the critical characteristic in reservoir development, especially for coalbed methane (CBM) reservoir. To investigate the permeability evolution during production in Shouyang CBM reservoir, Qinshui Basin, China, a new stress-sensitive permeability analytical model is proposed, while a time-lapse three-dimensional (4D) multi-physical coupling model is constructed. Heterogeneity and anisotropy of the reservoir flow and geomechanical properties as well as the permeability stress-sensitivity are adequately considered in the model. A coupling method is proposed to bridge data between finite difference (FD) grids and finite element (FE) grids with an interface code complied by Python. The reservoir flow data and geomechanical data are connected with each other by the interface code. Permeability stress-sensitivity experiments are carried out and compared with the numerical simulation results. According to the dynamic simulation results of 230 producing days, the stress increases with pore pressure decline, and the permeability stress-sensitivity is very strong in Shouyang 15# coalbed, especially in the initial stage of compression. The dynamic evolutions of stress and permeability are significantly affected by the anisotropy and heterogeneity of coalbed during depletion. The proposed stress-dependent permeability model is more suitable for characterizing the permeability evolution of the Shouyang CBM reservoir.

A new I2-mediated iodobenzannulation of yne-allenones has been established, enabling breaking/rearranging of C≡C bonds to selectively access 4-iodonaphthalen-1-ols with generally good yields. The resulting 4-iodonaphthalen-1-ols could serve as a new and reliable coupling reagent, which further reacted with H2O under the oxygen conditions to generate unexpected 1,2-carbonyls with good yields through Pd-catalyzed deiodinated carbonylation, whereas employment of benzene-1,2-diamine as the nucleophile rendered 3-(quinoxalin-2-yl)naphthalen-1-ols through Pd-catalyzed [4 + 2] heterocyclization. On the basis of the controlled experiments, the mechanism for forming 1,2-carbonyls was proposed, including an oxidative addition, 1,3-palladium migration, reductive elimination, and oxidative dehydrogenation sequence.

A new class of chiral N-sulfonyl bisimidazoline (Bim) ligands have been designed, prepared, and applied in Pd(II)-catalyzed asymmetric addition of arylboronic acids to isatin-derived N-Boc ketimines. The combination of Pd(OCOCF3)2 and N-tosyl Bim ligand shows high catalytic activity and excellent asymmetric induction, enabling asymmetric addition to offer α-tertiary amines with generally good to high yields and excellent enantioselectivity (up to 96% yield, 96% ee). This asymmetric Pd(II) catalysis can tolerate air conditions, providing a practical and operationally simple protocol toward the construction of an enantioenriched α-tertiary stereocenter.

Substrate-controlled generation of 3-sulfonylated 1-indenones and 3-arylated (Z)-indenes through radical cyclization cascades of o-alkynylbenzonitriles with sulfonyl hydrazides was established by combining copper(II) with tert-butyl hydroperoxide (TBHP) as a catalytic oxidative system. With the installation of the aryl group (R1) into the alkynyl unit, sulfonyl radicals triggered addition–cyclization cascades to access 3-sulfonylated 1-indenones with good yields by using a Cu/TBHP system, whereas a series of new functionalized 3-arylated (Z)-indenes were obtained in good yields when o-alkynylbenzonitriles bearing the alkyl group in the alkynyl unit were subjected with arylsulfonyl hydrazides with an electron-rich nature under the above conditions.

A new Pd(II)-catalyzed carbonyl-directing activation of alkenes has been established, enabling radical-induced selective fluorosulfonylation and aminosulfonylation of carbonyl-tethered 1,7-enynes with sulfinic acids and N-fluorobenzenesulfonimide (NFSI) under mild and redox neutral conditions to access densely functionalized ( E)-3,4-dihydronaphthalen-1(2 H)-ones with generally good yields and high stereoselectivity. The selectivity of these bifunctionalizations relies on the electronic nature of substituents on both aryl rings of 1,7-enynes.

A new sulfenylation reaction has been established, stereoselectively affording 37 examples of α-arylthio-α,β-unsaturated ketones with generally good yields via a metal-free three-component reaction of α-thiocyanate ketones with diaryliodonium salts and 1,2-dicarbonyls. The reaction enabled multiple bond-forming events including C(sp2)–S formation to provide a high-efficient and practical method toward α-arylthio-α,β-unsaturated ketones. The reasonable mechanism for forming α-arylthio-α,β-unsaturated ketones was proposed.

A new thiazolium salt-catalyzed [3 + 2 + 1] cyclization of acetylenedicarboxylates with arylglyoxals has been developed, enabling organocatalytic umpolung to access trisubstituted 2-pyrones with good yields via C–C bond cleavage, in which arylglyoxals played dual roles as a ring component as well as a carbonyl source. The reaction mechanism was proposed based on LC-MS analysis.

A new dehydrogenative [4 + 1] annulation of para-quinone methides (p-QMs) with acyclic and cyclic phenyl iodonium ylides has been established, delivering a variety of functionalized 2,3-dihydrobenzofurans with the retention of the quinone methide unit in generally good yields. The reaction pathway involves 1,6-nucleophilic addition, nucleophilic substitution and oxidation under mild metal-free and convenient conditions, and provides a practical access to construct benzofuran frameworks.

Authigenic clay (Aclay) is common in grain-supported tight reservoirs and exerts a primary control on reservoir’s percolation properties. In this study, we investigated the impacts of Aclay on pore connectivity, pore size distribution (PSD), and rock compressibility, to the resulting impacts on storage and percolation in order to arrive at a genetic classification of tight sandstones. QEMSCAN® combined with scanning electron microscopy was employed to identify the distribution and content of Aclay in a set of the Cretaceous tight gas sandstones, China. The size distribution of clay-related pores and their contributions to storage and percolation were distinguished from the interparticle pores by combining rate-controlled mercury porosimetry (RCP) and nuclear magnetic resonance (NMR). We found that Aclay evolved from predominantly pore-lining clays to predominantly pore-filling types as its content increased. Along this transition, clay-related pores gradually play a significant role in controlling the storage and percolation of tight sandstone reservoirs. There is very little change in pore volume and a sharp decrease in percolation threshold (PT) and permeability as Aclay content increases, which is mainly attributed to the dissolution that leads to the clay precipitation. On the other hand, compaction results in the reduction in PSD, porosity, PT and permeability together, however, the reduction rate caused by compaction become smaller as Aclay content increases, due to the limited compressibility of massive Aclay in grain-supported rocks. The hybrid effects of Aclay and compaction result in the formation of tight sandstones with various pore structures, corresponding to distinct pore types and reservoirs performances. We propose a threefold genetic classifications of tight sandstones: either from compaction alone, from Aclay cementation that plugs the original interparticle pores, or from a hybrid effect of these two processes.

A visible light photocatalytic methylsulfonylation/bicyclization of C(sp3)-tethered 1,7-enynes has been established using a dimethyl sulfoxide (DMSO)/H2O system as the methylsulfonyl source. This reaction worked readily to access a wide range of sulfone-containing benzo[a]fluoren-5-ones with one quaternary carbon centre and generally good yields through C–S bond cleavage of DMSO. The reaction mechanism was proposed based on the control experiments.

A new tunable Cu(I)-catalyzed site-selective dehydrogenative amination of β,γ-unsaturated hydrazones has been established using readily accessible dioxygen as a green oxidant. The presence of Cu2O/O2 regiospecifically accessed densely functionalized pyrazol-4-ones with one quaternary carbon-amino functionality, in which O2 acted as both a reaction component and an oxidant, whereas the employment of CuI/O2 as a catalytic oxidation system resulted in 1,6-dihydropyradazines with good yields.