A novel chemically-controlled [2]rotaxane molecular shuttle was successfully designed and synthesized. A H_2 S-responsive bulk barrier was introduced between the two identical recognition stations of the [2]rotaxane t...A novel chemically-controlled [2]rotaxane molecular shuttle was successfully designed and synthesized. A H_2 S-responsive bulk barrier was introduced between the two identical recognition stations of the [2]rotaxane to prevent dynamic shuttling of the macrocycle. Upon addition of H_2 S, the complete intramolecular cascade reaction occurs in a controllable manner, resulting in removal of the bulk barrier and the shuttling motion of the macrocycle between the two stations recovers.展开更多
Our recently studies on three types of reactions with hydrogen transfer as a key step,including catalytic asymmetric proton transfer reactions using"chiral proton transfer shuttle",catalytic B—H bond insert...Our recently studies on three types of reactions with hydrogen transfer as a key step,including catalytic asymmetric proton transfer reactions using"chiral proton transfer shuttle",catalytic B—H bond insertion containing a hydrogen atom transfer,and iron-catalyzed hydrosilylation reactions containing hydride transfer were briefly introduced.展开更多
Corrosion of iron-containing metals under sulfate-reducing conditions is an economically important problem.Microbial strains now known as Desulfovibrio vulgaris served as the model microbes in many of the foundational...Corrosion of iron-containing metals under sulfate-reducing conditions is an economically important problem.Microbial strains now known as Desulfovibrio vulgaris served as the model microbes in many of the foundational studies that developed existing models for the corrosion of iron-containing metals under sulfate-reducing conditions.Proposed mechanisms for corrosion by D.vulgaris include:(1)H2 consumption to accelerate the oxidation of Fe0 coupled to the reduction of protons to H2;(2)production of sulfide that combines with ferrous iron to form iron sulfide coatings that promote H2 production;(3)moribund cells release hydrogenases that catalyze Fe0 oxidation with the production of H2;(4)direct electron transfer from Fe0 to cells;and(5)flavins serving as an electron shuttle for electron transfer between Fe0 and cells.The demonstrated possibility of conducting transcriptomic and proteomic analysis of cells growing on metal surfaces suggests that similar studies on D.vulgaris corrosion biofilms can aid in identifying proteins that play an important role in corrosion.Tools for making targeted gene deletions in D.vulgaris are available for functional genetic studies.These approaches,coupled with instrumentation for the detection of low concentrations of H2,and proven techniques for evaluating putative electron shuttle function,are expected to make it possible to determine which of the proposed mechanisms for D.vulgaris corrosion are most important.展开更多
基金supported by the National Natural Science Foundation of China(21672060)the Fundamental Research Funds for the Central Universities(WJ1616011,WJ1213007,222201717003)the Programme of Introducing Talents of Discipline to Universities(B16017)
文摘A novel chemically-controlled [2]rotaxane molecular shuttle was successfully designed and synthesized. A H_2 S-responsive bulk barrier was introduced between the two identical recognition stations of the [2]rotaxane to prevent dynamic shuttling of the macrocycle. Upon addition of H_2 S, the complete intramolecular cascade reaction occurs in a controllable manner, resulting in removal of the bulk barrier and the shuttling motion of the macrocycle between the two stations recovers.
基金We thank the National Natural Science Foundation of China(21625204,21971119)the"111"project(B06005)of the Ministry of Education of China+2 种基金the National Program for Support of Top-notch Young Professionalsthe Key-Area Research and Development Program of Guangdong Province(2020B010188001)Frontiers Science Center for New Organic Matter of Nankai University(63181206)for financial support.
文摘Our recently studies on three types of reactions with hydrogen transfer as a key step,including catalytic asymmetric proton transfer reactions using"chiral proton transfer shuttle",catalytic B—H bond insertion containing a hydrogen atom transfer,and iron-catalyzed hydrosilylation reactions containing hydride transfer were briefly introduced.
文摘Corrosion of iron-containing metals under sulfate-reducing conditions is an economically important problem.Microbial strains now known as Desulfovibrio vulgaris served as the model microbes in many of the foundational studies that developed existing models for the corrosion of iron-containing metals under sulfate-reducing conditions.Proposed mechanisms for corrosion by D.vulgaris include:(1)H2 consumption to accelerate the oxidation of Fe0 coupled to the reduction of protons to H2;(2)production of sulfide that combines with ferrous iron to form iron sulfide coatings that promote H2 production;(3)moribund cells release hydrogenases that catalyze Fe0 oxidation with the production of H2;(4)direct electron transfer from Fe0 to cells;and(5)flavins serving as an electron shuttle for electron transfer between Fe0 and cells.The demonstrated possibility of conducting transcriptomic and proteomic analysis of cells growing on metal surfaces suggests that similar studies on D.vulgaris corrosion biofilms can aid in identifying proteins that play an important role in corrosion.Tools for making targeted gene deletions in D.vulgaris are available for functional genetic studies.These approaches,coupled with instrumentation for the detection of low concentrations of H2,and proven techniques for evaluating putative electron shuttle function,are expected to make it possible to determine which of the proposed mechanisms for D.vulgaris corrosion are most important.
