查看更多>>摘要：A general and broadly applicable copper and photoredox dual-catalyzed multicomponent 1,4-perfluoroalkylcyanation of 1,3-enynes has been developed.This protocol enjoys success with high regioselectivity,mild reaction conditions,and excellent functional-group tolerance,allowing the facile synthesis of structurally diverse perfluoroalkylated allenes from readily available fluoroalkyl halides,1,3-enynes and TMSCN in a one-pot manner.A reasonable mechanism has been proposed according to a series of control experi-ments.
查看更多>>摘要：A[2+1+1+1]cyclization reaction has been developed for the synthesis of multisubstituted β-pyrrolidinones from commercially available aryl methyl ketones,primary amines,and ethyl nitroacetate.In this l2-DMSO-meditated process,the C—NO2 bond of ethyl nitroacetate is cleaved,affording a C1 synthon,and the formation of two C—C and two C—N bonds and a quaternary carbon center are constructed in one pot.This method has good substrate compatibility and permits the late-stage modification of pharmaceutical compounds.
查看更多>>摘要：Copolymerization as an efficient strategy can provide an opportunity to create new closed-loop recyclable polymeric materials with tailored properties that are generally inaccessible to the individual homopolymers.In this contribution,the bulk ring-opening copol-ymerization of bio-renewable δ-caprolactone and trans-hexahydro-(4,5)-benzofuranone was achieved to produce closed-loop recy-clable copolyesters by using an organobase/urea binary catalyst at room temperature.The obtained copolyesters exhibited composi-tion-dependent thermal properties.Remarkably,the obtained copolyesters were able to depolymerize back to recover the corre-sponding monomers under mild conditions.The copolyesters with suitable compositions can be directly used as pressure-sensitive adhesives(PSAs)that possessed comparable peel strength with the commercially available PSA scotch tapes.When the copolyesters were mixed with plasticizers,the as-prepared PSAs exhibited desirable adhesive failure and can be used as removable post-it note.
查看更多>>摘要：Compounds with magnetic bistability is highly attractive for the construction of switches,thermal sensors,information-storage media and memory devices.Herein,we report a crystalline fullerene radical anion salt[Na(THF)5]C60(1),obtained by the reduction of C60 with Na in solution,which exhibits magnetic bistability accompanied with one magnetostructural transition,giving low temperature(LT),high temperature(HT)phases and a metastable phase.Fullerene radical anions(C60·-)in the structure were found arranged into a three-dimensional close-packed honeycomb subnetwork with hollow channels occupied by complex cations[Na(THF)s]+as spacers.The magnetic bistability is attributed to structural transitions as the LT-IT phase transition was associated with the orientational disorder of fullerene anions and the distortion of the complex cations[Na(THF)5]+in the 3D packing of fullerene anions.
查看更多>>摘要：An electrocatalytic multicomponent cascade cross-coupling for the synthesis of chalcogenosulfonates has been established.This ap-proach does not require the use of transition metals,acids,and external oxidants.The gentle conditions and tolerance to a wide vari-ety of functional groups permit the derivatization of complex indoles.
查看更多>>摘要：Chemical prelithiation is widely proven to be an effective strategy to address the low initial coulombic efficiency(ICE)of promising SiOx anode.Though the reagent composition has been widely explored,the Li+solvation structure,which practically plays the cornerstone role in the prelithiation ability,rate,uniformility,has rarely been explored.A novel environmentally-friendly reagent with weak solvent cyclopentyl methyl ether(CPME)is proposed that enables both improved ICE and spatial homogeneous solid electrolyte interphase(SEI).And the prelithiation behavior and mechanism were explored focused on the Li+solvation structure.Both theoretical investiga-tion and spectroscopic results suggest that weak solvent feature of CPME reduces the solvent coordination number and decreases the Li+desolvation energy.The optimized Li+solvation structure enables high-efficiency prelithiation that ensures the horizontal homoge-nization and mechanical properties of SEI.Moreover,the accompanied CPME molecules preferentially occupy positions in initial SEI,reducing the likelihood of LiPF6 decomposition and promoting longitudinal homogenization of SEI.Consequently,the efficient and homogenous prelithiation enables impressive ICE of 109.52％and improved cycling performance with 80.77％retained after 300 cycles via just 5 min soaking.Furthermore,the full cells with LiNi0.83Co0.12Mn0.05O2(NCM831205)cathode display an enhancement in the en-ergy density of 179.74％and up to 648.35 Wh·kg-1.
查看更多>>摘要：Polymer mechanochemistry has rapidly evolved since the mid-2000s.Recent advancements highlight the development of mech-anophore platforms for the controlled release of bioactive payloads and the exploration of biocompatible activation strategies.The-se platforms,ranging from furan-maleimide Diels-Alder adducts to disulfide motifs with β-carbonate linkages,demonstrate promis-ing prospects in targeted drug delivery.Additionally,supramolecular assemblies and free radical-generating mechanophores present innovative avenues for potential therapeutic applications.Biocompatible activation methods,notably high-intensity and/or low-intensity focused ultrasound,hold potential for in vivo applications.However,challenges persist in comprehending the funda-mental physics of ultrasound and its utilization for activation.Future directions emphasize the importance of simplicity in biocom-patible platforms and polymer designs,stability under physiological conditions,and precise control of mechanical activation for en-hanced biomedical and clinical utility.Despite the aforementioned chemical and technical obstacles,the outlook for polymer mech-anochemistry in biomedical and clinical applications remains promising,urging continued exploration and advancement.
查看更多>>摘要：Over the past few decades,N-sulfonyl hydrazones have been recognized as alternative precursors for hazardous diazo compounds in organic synthesis,allowing for diverse innovative and original chemical transformations that were otherwise difficult to achieve.This critical review summarizes the major advancements in the carbene chemistry of N-sulfonyl hydrazones.The contents of this review are organized based on research conducted by leading scientists who have made significant contributions to this field.The individual car-bene transfer reactions and their mechanisms,as well as the potential applications in the synthesis of natural products and complex bioactive molecules,are thoroughly discussed.
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