Carbocations such as tropylium and trityl cation, can be stable enough to be isolated and used without inert conditions. They can act as Lewis acids to lower the LUMO of electrophile, thus promoting reactions with nuc...Carbocations such as tropylium and trityl cation, can be stable enough to be isolated and used without inert conditions. They can act as Lewis acids to lower the LUMO of electrophile, thus promoting reactions with nucleophiles. Additionally, the interaction between carbocations and alcohols can form Bronsted acids with enhanced acidity. Furthermore, electrophoto activation of TAC^(+)(trisaminocyclopropenium ion)delivers the excited radical dication TAC·^(2+*), which is a strong oxidant and capable of oxidizing a range of challenging substrates. Moreover,^(n)Pr-DMQA^(+) is disclosed as a versatile photoredox catalyst as its excited state can be quenched through both oxidation and reduction. This review summarizes recent advance in carbocation-catalyzed reactions. These developed methods provide an environmentally friendly pathway for the synthesis of valuable compounds and will inspire chemists to discover more interesting transformations promoted by carbocations.展开更多
RDV■(dynamic vasoactive reactor)chemical technology represents a disruptive innovation operating under both surface and downhole conditions,producing irreversible and in situ adaptable effects.It has demonstrated tra...RDV■(dynamic vasoactive reactor)chemical technology represents a disruptive innovation operating under both surface and downhole conditions,producing irreversible and in situ adaptable effects.It has demonstrated transformative capacity across crude oils of various API gravities,with notable impact on extra-heavy crudes and bitumens,through a mechanism based on targeted proton donation that induces selective protonation of polar structures,generating transient carbocations that catalyze molecular fragmentation.This work presents a comprehensive analysis of the effects of RDV-DMG001■treatment(currently named RDV-01L■)on bitumen samples from the Primrose field,Alberta,Canada,using capillary chromatography,SARA analysis,and rheological evaluation,complemented with comparative data on prior applications of RDV-01L■in extra-heavy crudes from Venezuela(Boscán and El Salto).Results for Primrose bitumen show an 85%reduction in viscosity(from 500,000 to 75,000 cP),an increase in API gravity from 8.5 to 15.0(+76.4%),and molecular redistribution toward medium-chain hydrocarbons(C_(13)-C_(16)),with increases in molar and mass fractions up to 39.1%and 62.3%,respectively.SARA analysis confirmed fragmentation of asphaltenes(2.0%mass reduction)and a 5.8%increase in resins,improving colloidal stability and lowering precipitation risk.These changes align with RDV■’s mechanism of action based on carbocation generation.Notably,in field conditions-which are more dynamic and energetically favorable-RDV■treatment efficacy tends to exceed laboratory results,due to synergy among temperature,pressure,and fluid flow gradients which accelerate and enhance protonation and molecular fragmentation.Validated in contexts of advanced chemical transformation(Venezuela,Canada),the technology enables substantial improvements in fluidity,transport,processing,and recovery,with significant potential for annual cost savings in extraction and processing.This study positions RDV■as a disruptive,irreversible,and in situ adaptable chemical solution superior to conventional technologies such as surfactants,nanocatalysts,or aquathermolysis.RDV■is a quantum-impact chemical technology operating via molecular protonation reactions and controlled carbocation formation.The term“quantum”is used here as a conceptual analogy to describe the magnitude and specificity of the molecular reconfiguration induced by RDV■,without asserting direct experimental evidence of quantum reactivity.展开更多
This study documents pioneering results in marginal wells in Texas,where the application of RDV-00■restored production through delayed protonic activation catalyzed by reservoir energy.The product,based on RDV■(Vaso...This study documents pioneering results in marginal wells in Texas,where the application of RDV-00■restored production through delayed protonic activation catalyzed by reservoir energy.The product,based on RDV■(Vasoactive Dynamic Reactor)technology,operates via:Controlled protonation of molecular structures;Release of energetic carbocations;Autonomous transformation without external inputs.(a)Case 1(Well#E2-Starr County):Certified as“dry”by RRC(2022)after 48 months at 0 BPD;8 months post-injection of 5 gal RDV-00■(Fluid column:37 bbl;Wellhead pressure:80 psi(vs.0 psi initially)).(b)Case 2(Well#P1-Luling Field):Historical stripper well(0.25-0.5 BPD);23 months of immobilization with 15 gal RDV-00■;Critical results:(1)Initial production:42 BPD(8,400%above baseline);(2)Shut-in wellhead pressure:40 psi(neighboring wells=0-3 psi);(3)Current behavior:Continuous recharge from reservoir(well shut-in due to lack of storage).(c)Technically Significant Observations:(1)First case of self-sustaining reactivation in depleted wells;(2)Mechanism validated by Autonomous pressure generation(0→40-80 psi),and Continuous flow without additional stimulation;(3)No documented precedents in SPE/OnePetro literature to our knowledge.展开更多
The first transition metal-free highly stereoselective positional isomerization of various α-alkyl styrenes through a carbocation mech-anism triggered strategy is developed by using AI(OTf)_(3) as a hidden Br0nsted a...The first transition metal-free highly stereoselective positional isomerization of various α-alkyl styrenes through a carbocation mech-anism triggered strategy is developed by using AI(OTf)_(3) as a hidden Br0nsted acid catalyst,which provides facile access to value-added acyclic tri-and tetra-substituted alkenes in good yields with high stereoselectivity under mild conditions.展开更多
The carbocationic polymerization of styrene(St) initiated by H2O/TiCl4 system was conducted at-60℃ in dichloromethane(CH2Cl2)/hexane(n-Hex)(50/50 V/V) in the presence of pyridine(Py),2-methyl pyridine(MPy...The carbocationic polymerization of styrene(St) initiated by H2O/TiCl4 system was conducted at-60℃ in dichloromethane(CH2Cl2)/hexane(n-Hex)(50/50 V/V) in the presence of pyridine(Py),2-methyl pyridine(MPy) and 2,6-dimethyl pyridine(DMPy).A desirable polymerization process with a relative slow polymerization rate and PS products with relatively narrow molecular weight distribution(MWD,Mw/Mn ca.1.8) were obtained.Py and its derivants and/or their complexes with Lewis acid TiCl4 interact with the growing chain end to reduced its 'cationicity' and thus to decrease the polymerization rate,suppress chain transfer and termination reactions and narrow MWD.The experimental results also show that the monomer conversion as well as the molecular weight of polymer products increased but MWD almost kept unchanged with polymerization time.The number-average molecular weight of polymer increased linearly with monomer conversion but the line did not pass through the origin.展开更多
篢he carbocationic reaction between 2, 4, 4-trimethy1-2-chloropentane, which is a model compound of polyisobutylene’s end group, and 1, ldsdiphenyl ethylene was investigated by high pressure liquid chromatography, it...篢he carbocationic reaction between 2, 4, 4-trimethy1-2-chloropentane, which is a model compound of polyisobutylene’s end group, and 1, ldsdiphenyl ethylene was investigated by high pressure liquid chromatography, it was found that the reaction presents a strong reverse reaction even if at low temperature. The ceiling temperature is about -18℃. The reaction with tirne and effect of concentration of TiCl4, temperature, polarity of solvent on the reaction show that the main features of this reaction are very close to that of carbocationic polymerization of isobutylene. So the reaction would be ideal model reaction for the carbocationic polymerization.展开更多
This article is based on the experimental data on reaction of FCC naphtha in the presence of acid catalysts. The data published in the literature were reprocessed and compared with experimental data and the relationsh...This article is based on the experimental data on reaction of FCC naphtha in the presence of acid catalysts. The data published in the literature were reprocessed and compared with experimental data and the relationship of hydrogen and methane contained in the dry gas with the conversion rate was identified.The similarity between the route for cracking of olefin enriched FCC gasoline and the route for reaction of individual hydrocarbons was deduced, while the route for formation of ethylene in dry gas was also proposed to identify the relationship between the reaction path for formation of ethylene and the conversion rate.展开更多
In order to investigate the impact of U-ore on organic matter maturation and isotopic fractionation,we designed hydrous pyrolysis experiments on Type-II kerogen samples,supposing that the water and water–mineral inte...In order to investigate the impact of U-ore on organic matter maturation and isotopic fractionation,we designed hydrous pyrolysis experiments on Type-II kerogen samples,supposing that the water and water–mineral interaction play a role.U-ore was set as the variable for comparison.Meanwhile,anhydrous pyrolysis under the same conditions was carried out as the control experiments.The determination of liquid products indicates that the presence of water and minerals obviously enhanced the yields of C(15+) and the amounts of hydrocarbon and nonhydrocarbon gases.Such results may be attributed to waterorganic matter reaction in the high-temperature system,which can provide additional hydrogen and oxygen for the generation of gas and liquid products from organic matter.It is found that δD values of hydrocarbon gases generated in both hydrous pyrolysis experiments are much lower than those in anhydrous pyrolysis.What is more,δD values are lower in the hydrous pyrolysis with uranium ore.Therefore,we can infer that water-derived hydrogen played a significant role during the kerogen thermal evolution and the hydrocarbon generation in our experiments.Isotopic exchange was facilitated by the reversible equilibration between reaction intermediaries with hydrogen under hydrothermal conditions with uranium ore.Carbon isotopic fractionations of hydrocarbon gases were somehow affected by the presence of water and the uranium ore.The increased level of i-C4/n-C4ratios for gas products in hydrous pyrolysis implied the carbocation mechanism for water-kerogen reactions.展开更多
This work investigates the effect of reaction conditions on the copolymerization of isobutylene (IB) with alloocimene (Allo) in methyl chloride (MeCl) using AlCh and ethylaluminum dichloride (EtAlCh) as coinitiators a...This work investigates the effect of reaction conditions on the copolymerization of isobutylene (IB) with alloocimene (Allo) in methyl chloride (MeCl) using AlCh and ethylaluminum dichloride (EtAlCh) as coinitiators and adventitious moisture as the initiator. Both AlCh and EtAlCb produced high molecular weight (Mn > 1.0 x 10^5 g/mol) thermoplastic elastomers (TPEs) with good mechanical properties in short reaction time (< 10 min). These unique TPEs have unsaturations in the end blocks, leading to easy functionalization and/or crosslinking.展开更多
基金Financial support from National Natural Science Foundation of China (No. 21871053)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang (No. 2019R01005)the Open Research Fund of School of Chemistry and Chemical Engineering, Henan Normal University (No. 2020ZD04) is gratefully acknowledged。
文摘Carbocations such as tropylium and trityl cation, can be stable enough to be isolated and used without inert conditions. They can act as Lewis acids to lower the LUMO of electrophile, thus promoting reactions with nucleophiles. Additionally, the interaction between carbocations and alcohols can form Bronsted acids with enhanced acidity. Furthermore, electrophoto activation of TAC^(+)(trisaminocyclopropenium ion)delivers the excited radical dication TAC·^(2+*), which is a strong oxidant and capable of oxidizing a range of challenging substrates. Moreover,^(n)Pr-DMQA^(+) is disclosed as a versatile photoredox catalyst as its excited state can be quenched through both oxidation and reduction. This review summarizes recent advance in carbocation-catalyzed reactions. These developed methods provide an environmentally friendly pathway for the synthesis of valuable compounds and will inspire chemists to discover more interesting transformations promoted by carbocations.
文摘RDV■(dynamic vasoactive reactor)chemical technology represents a disruptive innovation operating under both surface and downhole conditions,producing irreversible and in situ adaptable effects.It has demonstrated transformative capacity across crude oils of various API gravities,with notable impact on extra-heavy crudes and bitumens,through a mechanism based on targeted proton donation that induces selective protonation of polar structures,generating transient carbocations that catalyze molecular fragmentation.This work presents a comprehensive analysis of the effects of RDV-DMG001■treatment(currently named RDV-01L■)on bitumen samples from the Primrose field,Alberta,Canada,using capillary chromatography,SARA analysis,and rheological evaluation,complemented with comparative data on prior applications of RDV-01L■in extra-heavy crudes from Venezuela(Boscán and El Salto).Results for Primrose bitumen show an 85%reduction in viscosity(from 500,000 to 75,000 cP),an increase in API gravity from 8.5 to 15.0(+76.4%),and molecular redistribution toward medium-chain hydrocarbons(C_(13)-C_(16)),with increases in molar and mass fractions up to 39.1%and 62.3%,respectively.SARA analysis confirmed fragmentation of asphaltenes(2.0%mass reduction)and a 5.8%increase in resins,improving colloidal stability and lowering precipitation risk.These changes align with RDV■’s mechanism of action based on carbocation generation.Notably,in field conditions-which are more dynamic and energetically favorable-RDV■treatment efficacy tends to exceed laboratory results,due to synergy among temperature,pressure,and fluid flow gradients which accelerate and enhance protonation and molecular fragmentation.Validated in contexts of advanced chemical transformation(Venezuela,Canada),the technology enables substantial improvements in fluidity,transport,processing,and recovery,with significant potential for annual cost savings in extraction and processing.This study positions RDV■as a disruptive,irreversible,and in situ adaptable chemical solution superior to conventional technologies such as surfactants,nanocatalysts,or aquathermolysis.RDV■is a quantum-impact chemical technology operating via molecular protonation reactions and controlled carbocation formation.The term“quantum”is used here as a conceptual analogy to describe the magnitude and specificity of the molecular reconfiguration induced by RDV■,without asserting direct experimental evidence of quantum reactivity.
文摘This study documents pioneering results in marginal wells in Texas,where the application of RDV-00■restored production through delayed protonic activation catalyzed by reservoir energy.The product,based on RDV■(Vasoactive Dynamic Reactor)technology,operates via:Controlled protonation of molecular structures;Release of energetic carbocations;Autonomous transformation without external inputs.(a)Case 1(Well#E2-Starr County):Certified as“dry”by RRC(2022)after 48 months at 0 BPD;8 months post-injection of 5 gal RDV-00■(Fluid column:37 bbl;Wellhead pressure:80 psi(vs.0 psi initially)).(b)Case 2(Well#P1-Luling Field):Historical stripper well(0.25-0.5 BPD);23 months of immobilization with 15 gal RDV-00■;Critical results:(1)Initial production:42 BPD(8,400%above baseline);(2)Shut-in wellhead pressure:40 psi(neighboring wells=0-3 psi);(3)Current behavior:Continuous recharge from reservoir(well shut-in due to lack of storage).(c)Technically Significant Observations:(1)First case of self-sustaining reactivation in depleted wells;(2)Mechanism validated by Autonomous pressure generation(0→40-80 psi),and Continuous flow without additional stimulation;(3)No documented precedents in SPE/OnePetro literature to our knowledge.
基金We gratefully acknowledge the financial support from the National Natural Science Foundation of China(Grant No.21901074)"Zijiang Scholar Program"of East China Normal University。
文摘The first transition metal-free highly stereoselective positional isomerization of various α-alkyl styrenes through a carbocation mech-anism triggered strategy is developed by using AI(OTf)_(3) as a hidden Br0nsted acid catalyst,which provides facile access to value-added acyclic tri-and tetra-substituted alkenes in good yields with high stereoselectivity under mild conditions.
文摘The carbocationic polymerization of styrene(St) initiated by H2O/TiCl4 system was conducted at-60℃ in dichloromethane(CH2Cl2)/hexane(n-Hex)(50/50 V/V) in the presence of pyridine(Py),2-methyl pyridine(MPy) and 2,6-dimethyl pyridine(DMPy).A desirable polymerization process with a relative slow polymerization rate and PS products with relatively narrow molecular weight distribution(MWD,Mw/Mn ca.1.8) were obtained.Py and its derivants and/or their complexes with Lewis acid TiCl4 interact with the growing chain end to reduced its 'cationicity' and thus to decrease the polymerization rate,suppress chain transfer and termination reactions and narrow MWD.The experimental results also show that the monomer conversion as well as the molecular weight of polymer products increased but MWD almost kept unchanged with polymerization time.The number-average molecular weight of polymer increased linearly with monomer conversion but the line did not pass through the origin.
文摘篢he carbocationic reaction between 2, 4, 4-trimethy1-2-chloropentane, which is a model compound of polyisobutylene’s end group, and 1, ldsdiphenyl ethylene was investigated by high pressure liquid chromatography, it was found that the reaction presents a strong reverse reaction even if at low temperature. The ceiling temperature is about -18℃. The reaction with tirne and effect of concentration of TiCl4, temperature, polarity of solvent on the reaction show that the main features of this reaction are very close to that of carbocationic polymerization of isobutylene. So the reaction would be ideal model reaction for the carbocationic polymerization.
文摘This article is based on the experimental data on reaction of FCC naphtha in the presence of acid catalysts. The data published in the literature were reprocessed and compared with experimental data and the relationship of hydrogen and methane contained in the dry gas with the conversion rate was identified.The similarity between the route for cracking of olefin enriched FCC gasoline and the route for reaction of individual hydrocarbons was deduced, while the route for formation of ethylene in dry gas was also proposed to identify the relationship between the reaction path for formation of ethylene and the conversion rate.
文摘In order to investigate the impact of U-ore on organic matter maturation and isotopic fractionation,we designed hydrous pyrolysis experiments on Type-II kerogen samples,supposing that the water and water–mineral interaction play a role.U-ore was set as the variable for comparison.Meanwhile,anhydrous pyrolysis under the same conditions was carried out as the control experiments.The determination of liquid products indicates that the presence of water and minerals obviously enhanced the yields of C(15+) and the amounts of hydrocarbon and nonhydrocarbon gases.Such results may be attributed to waterorganic matter reaction in the high-temperature system,which can provide additional hydrogen and oxygen for the generation of gas and liquid products from organic matter.It is found that δD values of hydrocarbon gases generated in both hydrous pyrolysis experiments are much lower than those in anhydrous pyrolysis.What is more,δD values are lower in the hydrous pyrolysis with uranium ore.Therefore,we can infer that water-derived hydrogen played a significant role during the kerogen thermal evolution and the hydrocarbon generation in our experiments.Isotopic exchange was facilitated by the reversible equilibration between reaction intermediaries with hydrogen under hydrothermal conditions with uranium ore.Carbon isotopic fractionations of hydrocarbon gases were somehow affected by the presence of water and the uranium ore.The increased level of i-C4/n-C4ratios for gas products in hydrous pyrolysis implied the carbocation mechanism for water-kerogen reactions.
基金financially supported by the National Science Foundation (No. IIP-1434014) (Accelerating Innovation Research)Support by the Breast Cancer Innovation Foundation was also acknowledged
文摘This work investigates the effect of reaction conditions on the copolymerization of isobutylene (IB) with alloocimene (Allo) in methyl chloride (MeCl) using AlCh and ethylaluminum dichloride (EtAlCh) as coinitiators and adventitious moisture as the initiator. Both AlCh and EtAlCb produced high molecular weight (Mn > 1.0 x 10^5 g/mol) thermoplastic elastomers (TPEs) with good mechanical properties in short reaction time (< 10 min). These unique TPEs have unsaturations in the end blocks, leading to easy functionalization and/or crosslinking.