The commercial exploitation of unconventional petroleum resources(e.g.,shale oil/gas and tight oil/gas)has drastically changed the global energy structure within the past two decades.Sweet-spot intervals(areas),the mo...The commercial exploitation of unconventional petroleum resources(e.g.,shale oil/gas and tight oil/gas)has drastically changed the global energy structure within the past two decades.Sweet-spot intervals(areas),the most prolific unconventional hydrocarbon resources,generally consist of extraordinarily high organic matter(EHOM)deposits or closely associated sandstones/carbonate rocks.The formation of sweet-spot intervals(areas)is fundamentally controlled by their depositional and subsequent diagenetic settings,which result from the coupled sedimentation of global or regional geological events,such as tectonic activity,sea level(lake level)fluctuations,climate change,bottom water anoxia,volcanic activity,biotic mass extinction or radiation,and gravity flows during a certain geological period.Black shales with EHOM content and their associated high-quality reservoir rocks deposited by the coupling of major geological events provide not only a prerequisite for massive hydrocarbon generation but also abundant hydrocarbon storage space.The Ordovician-Silurian Wufeng-Longmaxi shale of the Sichuan Basin,Devonian Marcellus shale of the Appalachian Basin,Devonian-Carboniferous Bakken Formation of the Williston Basin,and Triassic Yanchang Formation of the Ordos Basin are four typical unconventional hydrocarbon systems selected as case studies herein.In each case,the formation of sweet-spot intervals for unconventional hydrocarbon resources was controlled by the coupled sedimentation of different global or regional geological events,collectively resulting in a favorable environment for the production,preservation,and accumulation of organic matter,as well as for the generation,migration,accumulation,and exploitation of hydrocarbons.Unconventional petroleum sedimentology,which focuses on coupled sedimentation during dramatic environmental changes driven by major geological events,is key to improve the understanding of the formation and distribution of sweet-spot intervals(areas)in unconventional petroleum systems.展开更多
There are very limited approaches to directly gluing two molecules for the production of internal alkenes using the vastly abundant acetylene via 1,2-difunctionalization. Conversion of gaseous acetylene to internal al...There are very limited approaches to directly gluing two molecules for the production of internal alkenes using the vastly abundant acetylene via 1,2-difunctionalization. Conversion of gaseous acetylene to internal alkenes via 1,2-difunctionalization in a desired manner is not as easy as it might be expected due to the potential competition reactions between acetylene and alkene produced and the difficulty in handling this harmful reagent and controlling the regio-and stereoselectivity. In this work, we designed an efficient catalytic system for the incorporation of acetylene gas into tremendous(E)-β-bromo vinylsulfones, which are bench-stable, easy to operate, and can function as bifunctional acetylene and show a rich reactivity profile in Sonogashira coupling, Heck coupling, substituted reaction, and various desulfonylation transformations, providing numerous internal alkenes.展开更多
Conjugated polyene motifs are ubiquitous in various natural products and functional molecules;however,their synthesis is very challenging because of the required lengthy and time-consuming processes.We herein report a...Conjugated polyene motifs are ubiquitous in various natural products and functional molecules;however,their synthesis is very challenging because of the required lengthy and time-consuming processes.We herein report an efficient approach for the synthesis of(E,E)-trienes via cationic rhodium catalysis using acetylene and simple alkenes bearing diverse directing groups as the starting materials.The reaction featured high step economy,excellent functional group compatibility,and exclusive stereoselectivity.Various directing groups such as carbonyl,sulfone,phosphate,hydroxyl,and amino were compatible.Furthermore,the triene products allowed versatile elaborations,providing rapid and convenient access to several important bioactive molecules,including vitamin A,(+)-roxaticin,and other complex polyenes.Mechanistic experiments showed that the directing group on the alkene played a crucial role in the reaction.展开更多
A TEMPO catalyzed cross-dihalogenation reaction was established via redox-regulation of the otherwise complex system of dual electrophilic X+reagents.Formally,the ICl,BrCl,I_(2) and Br_(2) were generated in-situ,which...A TEMPO catalyzed cross-dihalogenation reaction was established via redox-regulation of the otherwise complex system of dual electrophilic X+reagents.Formally,the ICl,BrCl,I_(2) and Br_(2) were generated in-situ,which enabled high regio-or stereoselective access to a myriad of iodochlorination,bromochlorination and homo-dihalogenation products with a wide spectrum of functionalities.With its mild conditions and operational simplicity,this method could enable wide applications in organic synthesis,which was exemplified by divergent synthesis of two pharmaceuticals.Detailed mechanistic investigations via radical clock reaction,pinacol ring expansion and Hammett experiments were conducted,which confirmed the intermediacy of halonium ion.In addition,a dynamic catalytic model based on the versatile catalytic role of TEMPO was proposed to explain the selective outcomes.展开更多
We report the first Rh2(II)-catalyzed asymmetric cycloisomerization of activated enynes to provide cyclopropane-fused tetrahydropyridines in good yields and excellent enantioselectivities under mild conditions.The act...We report the first Rh2(II)-catalyzed asymmetric cycloisomerization of activated enynes to provide cyclopropane-fused tetrahydropyridines in good yields and excellent enantioselectivities under mild conditions.The activated group,CHZ(Z is electronwithdrawing group(EWG)),in the enyne substrates exerts two synergetic roles,one is to activate alkyne for the cyclopropanation reaction;the other is to introduce the C–H…O interaction between substrate and catalyst(reducing the energy barrier of the reaction).This double-mode activation was supported by both density functional theory(DFT)calculations and experimental tests.This strategy was also extended to other CH2 Z(Z can be OH,OMe,F)as activating groups that made the CH2 more acidic so that the substrates could also form increased C–H…O interaction with the catalyst.展开更多
Summary of main observation and conclusion A Cu(I)-catalyzed three-component reaction of terminal enynals/enynones,diazo compounds,and al kenes has been developed.With this method,a series of oxabicyclo[2.2.2]octanes ...Summary of main observation and conclusion A Cu(I)-catalyzed three-component reaction of terminal enynals/enynones,diazo compounds,and al kenes has been developed.With this method,a series of oxabicyclo[2.2.2]octanes were effectively synthesized in high yields under mild reaction condi-tions.This transformation is proposed to proceed through trapping of the cyclic vinyl-o-quinodimethanes(vinyI-o-QDMs)species,which were generated from terminal enynals/enynones and diazo compounds by alkenes.The obvious advantages of wide substrate scopes,mild reaction conditions,and high seteroselectivity and atom eficiency make this reaction highly appealing for construction of highly rigid[2.2.2]octane skeleton.展开更多
A highly efficient redox-and step-economic method to synthesize N,O-and O,O-difluoroboron complexes from alkynes under aqueous condition with HBF_(4) as BF_(2) source has been developed.This strategy features good yie...A highly efficient redox-and step-economic method to synthesize N,O-and O,O-difluoroboron complexes from alkynes under aqueous condition with HBF_(4) as BF_(2) source has been developed.This strategy features good yields,broad substrate scope,mild reaction conditions,readily available starting materials and gram-scale synthesis.Significantly,these difluoroboron complexes present good fluorescence properties,indicating their potential applications in luminescent materials.展开更多
基金jointly supported by the Scientific Research and Technological Development Programs of CNPC(2021yjcq02 and 2021DJ2001)。
文摘The commercial exploitation of unconventional petroleum resources(e.g.,shale oil/gas and tight oil/gas)has drastically changed the global energy structure within the past two decades.Sweet-spot intervals(areas),the most prolific unconventional hydrocarbon resources,generally consist of extraordinarily high organic matter(EHOM)deposits or closely associated sandstones/carbonate rocks.The formation of sweet-spot intervals(areas)is fundamentally controlled by their depositional and subsequent diagenetic settings,which result from the coupled sedimentation of global or regional geological events,such as tectonic activity,sea level(lake level)fluctuations,climate change,bottom water anoxia,volcanic activity,biotic mass extinction or radiation,and gravity flows during a certain geological period.Black shales with EHOM content and their associated high-quality reservoir rocks deposited by the coupling of major geological events provide not only a prerequisite for massive hydrocarbon generation but also abundant hydrocarbon storage space.The Ordovician-Silurian Wufeng-Longmaxi shale of the Sichuan Basin,Devonian Marcellus shale of the Appalachian Basin,Devonian-Carboniferous Bakken Formation of the Williston Basin,and Triassic Yanchang Formation of the Ordos Basin are four typical unconventional hydrocarbon systems selected as case studies herein.In each case,the formation of sweet-spot intervals for unconventional hydrocarbon resources was controlled by the coupled sedimentation of different global or regional geological events,collectively resulting in a favorable environment for the production,preservation,and accumulation of organic matter,as well as for the generation,migration,accumulation,and exploitation of hydrocarbons.Unconventional petroleum sedimentology,which focuses on coupled sedimentation during dramatic environmental changes driven by major geological events,is key to improve the understanding of the formation and distribution of sweet-spot intervals(areas)in unconventional petroleum systems.
基金supported by the National Natural Science Foundation of China(22001079,22271096,22071062,21871096)the China Postdoctoral Science Foundation(2020M682694)。
文摘There are very limited approaches to directly gluing two molecules for the production of internal alkenes using the vastly abundant acetylene via 1,2-difunctionalization. Conversion of gaseous acetylene to internal alkenes via 1,2-difunctionalization in a desired manner is not as easy as it might be expected due to the potential competition reactions between acetylene and alkene produced and the difficulty in handling this harmful reagent and controlling the regio-and stereoselectivity. In this work, we designed an efficient catalytic system for the incorporation of acetylene gas into tremendous(E)-β-bromo vinylsulfones, which are bench-stable, easy to operate, and can function as bifunctional acetylene and show a rich reactivity profile in Sonogashira coupling, Heck coupling, substituted reaction, and various desulfonylation transformations, providing numerous internal alkenes.
基金the NSFC(grant nos.21871096,22071062,22271096),and the Fundamental Research Funds for the Central Universities,SCUT.
文摘Conjugated polyene motifs are ubiquitous in various natural products and functional molecules;however,their synthesis is very challenging because of the required lengthy and time-consuming processes.We herein report an efficient approach for the synthesis of(E,E)-trienes via cationic rhodium catalysis using acetylene and simple alkenes bearing diverse directing groups as the starting materials.The reaction featured high step economy,excellent functional group compatibility,and exclusive stereoselectivity.Various directing groups such as carbonyl,sulfone,phosphate,hydroxyl,and amino were compatible.Furthermore,the triene products allowed versatile elaborations,providing rapid and convenient access to several important bioactive molecules,including vitamin A,(+)-roxaticin,and other complex polyenes.Mechanistic experiments showed that the directing group on the alkene played a crucial role in the reaction.
基金financial support from the NSFC(Nos.21871096,22071062,22001077)the Ministry of Science and Technology of the People’s Republic of China(No.2016YFA0602900)+1 种基金the Guangdong Science and Technology Department(Nos.2018B030308007,2021A1515012331)the China Postdoctoral Science Foundation(Nos.2018M643062,2019T120723).
文摘A TEMPO catalyzed cross-dihalogenation reaction was established via redox-regulation of the otherwise complex system of dual electrophilic X+reagents.Formally,the ICl,BrCl,I_(2) and Br_(2) were generated in-situ,which enabled high regio-or stereoselective access to a myriad of iodochlorination,bromochlorination and homo-dihalogenation products with a wide spectrum of functionalities.With its mild conditions and operational simplicity,this method could enable wide applications in organic synthesis,which was exemplified by divergent synthesis of two pharmaceuticals.Detailed mechanistic investigations via radical clock reaction,pinacol ring expansion and Hammett experiments were conducted,which confirmed the intermediacy of halonium ion.In addition,a dynamic catalytic model based on the versatile catalytic role of TEMPO was proposed to explain the selective outcomes.
基金the National Natural Science Foundation of China(2187109621672071+7 种基金91856105)the Ministry of Science and Technology of China(2016YFA0602900)the Natural Science Foundation of Guangdong(2018B0303080072018A0303103592016A030310433)the Science and Technology Program of Guangzhou(201707010316)the Fundamental Research Funds for the Central UniversitiesSouth China University of Technology。
文摘We report the first Rh2(II)-catalyzed asymmetric cycloisomerization of activated enynes to provide cyclopropane-fused tetrahydropyridines in good yields and excellent enantioselectivities under mild conditions.The activated group,CHZ(Z is electronwithdrawing group(EWG)),in the enyne substrates exerts two synergetic roles,one is to activate alkyne for the cyclopropanation reaction;the other is to introduce the C–H…O interaction between substrate and catalyst(reducing the energy barrier of the reaction).This double-mode activation was supported by both density functional theory(DFT)calculations and experimental tests.This strategy was also extended to other CH2 Z(Z can be OH,OMe,F)as activating groups that made the CH2 more acidic so that the substrates could also form increased C–H…O interaction with the catalyst.
基金We appreciate financial support from Ministry of Science and Technology of the People's Republic of China(2016YFA0602900)the National Natural Science Foundation of China(21871096,21672071)+1 种基金Guangdong Science and Technology Department(20188030308007,2018A030310359,2016A030310433)the Science and Technology Program of Guangzhou(201707010316,201707010168).
文摘Summary of main observation and conclusion A Cu(I)-catalyzed three-component reaction of terminal enynals/enynones,diazo compounds,and al kenes has been developed.With this method,a series of oxabicyclo[2.2.2]octanes were effectively synthesized in high yields under mild reaction condi-tions.This transformation is proposed to proceed through trapping of the cyclic vinyl-o-quinodimethanes(vinyI-o-QDMs)species,which were generated from terminal enynals/enynones and diazo compounds by alkenes.The obvious advantages of wide substrate scopes,mild reaction conditions,and high seteroselectivity and atom eficiency make this reaction highly appealing for construction of highly rigid[2.2.2]octane skeleton.
基金This work was supported by the NSFC(Nos.22071062,21871096,22001077)the Ministry of Science and Technology of the People's Republic of China(No.2016YFA0602900)+1 种基金Guangdong Science and Technology Department(Nos.2018B030308007,2021A1515012331)the China Postdoctoral Science Foundation(Nos.2018M643062,2019T120723).
文摘A highly efficient redox-and step-economic method to synthesize N,O-and O,O-difluoroboron complexes from alkynes under aqueous condition with HBF_(4) as BF_(2) source has been developed.This strategy features good yields,broad substrate scope,mild reaction conditions,readily available starting materials and gram-scale synthesis.Significantly,these difluoroboron complexes present good fluorescence properties,indicating their potential applications in luminescent materials.