The chemo-,regio-,and enantio-controlled synthesis of P-chiral phosphines in a general and efficient manner remains a significant synthetic challenge.In this study,a Pd-catalyzed hydrofunctionalization is developed fo...The chemo-,regio-,and enantio-controlled synthesis of P-chiral phosphines in a general and efficient manner remains a significant synthetic challenge.In this study,a Pd-catalyzed hydrofunctionalization is developed for the highly selective synthesis of P-stereogenic alkenylphosphinates and alkenylphosphine oxides via conjugate addition of enynes.Notably,this methodology is suitable for both phosphine oxide and phosphinate nucleophiles,providing a versatile approach for the construction of diverse P-chiral organophosphosphorus compound.展开更多
Herein,we developed the first example of copper-catalyzed silicon radical-initiated 1,4-silylcyanation of unactivated 1,3-enynes,which provided an efficient method to access CN-bearing tri-and tetrasubstituted homoall...Herein,we developed the first example of copper-catalyzed silicon radical-initiated 1,4-silylcyanation of unactivated 1,3-enynes,which provided an efficient method to access CN-bearing tri-and tetrasubstituted homoallenylsilane derivatives in high yields with excellent regioselectivities.This protocol featured good functional group compatibility and broad substrate scopes,enabling the formation of C-Si bond under cheap copper catalyst with a low loading.Furthermore,this means showed potential application value in the late-stage functionalization of natural products.展开更多
Hybrid quantum mechanics/molecular mechanics calculations were performed to elucidate how[Mn^(Ⅲ)porphyrin]^(+X−)-based metal-organic frameworks(MOFs)catalyze the[2+1]cycloisomerization of enynes and why zwitterionic ...Hybrid quantum mechanics/molecular mechanics calculations were performed to elucidate how[Mn^(Ⅲ)porphyrin]^(+X−)-based metal-organic frameworks(MOFs)catalyze the[2+1]cycloisomerization of enynes and why zwitterionic MOFs exhibit strong activity in Lewis acid catalysis.The calculations showed that zwitterionic MOFs have a“pure cationic active center”leading to a concerted nucleophilic attack pathway with lower barriers.In contrast,metals with coordinating anions have reduced electrophilicity,resulting in a stepwise radical-type pathway with much higher barriers.Further calculations showed the nature of catalysis was strongly depended on the charge on the anion ligand.A good linear relationship between the NPA charge and barrier was found,and verified by 73 anions with small derivations,which presents a universal adaptive character for various coordinated anions.展开更多
Polyhydroxy enyne compound （＋）-（1＇S, 2R, 3S, 5S, 6S）-5,6-dimethoxy-5, 6-dimethyl- 2-（1＇-hydroxylpropyl-2-ne）-3-vinyl-l,4-dioxane has been synthesized from D-（-）-tartaric acid. A new chiral center was establ...Polyhydroxy enyne compound （＋）-（1＇S, 2R, 3S, 5S, 6S）-5,6-dimethoxy-5, 6-dimethyl- 2-（1＇-hydroxylpropyl-2-ne）-3-vinyl-l,4-dioxane has been synthesized from D-（-）-tartaric acid. A new chiral center was established by nucleophilic addition with 87% de. The modified Mosher＇s method was employed to confirm the absolute configuration of 17, which assigned the S-configuration at the new chiral center.展开更多
A regiodivergent hydrophosphorylation of enynes with phosphites has been developed using earthabundant nickel catalyst.The manipulation of regioselectivity can be achieved by regulating the insertion order of alkyne b...A regiodivergent hydrophosphorylation of enynes with phosphites has been developed using earthabundant nickel catalyst.The manipulation of regioselectivity can be achieved by regulating the insertion order of alkyne bonds with(RO)_(2)P(O)-Ni-H or R_(2)P(O)O-Ni-H species,respectively.Under the Ni/Xantphos catalysis,4,1-hydrophosphorylation is selectively obtained while the adding of acid can promote reactions towards 1,2-addition.By employing an additional Pd-H catalysis,2,1-hydrophosphorylation is also an accessible task in one-pot reaction.Mechanistic studies and analysis have also been performed to interpret the origin of the regioselective regulation.This work highlights the arts in accessing different regioisomers by diverting common elementary reaction steps.展开更多
Herein,a highly enantioselective formal synthesis of(+)-Treprostinil via the interphenylene prostaglandin E1 scaffold was described.The chiral multi-substituted cyclopentanone was constructed via a[Rh(Duanphos)SbF6-ca...Herein,a highly enantioselective formal synthesis of(+)-Treprostinil via the interphenylene prostaglandin E1 scaffold was described.The chiral multi-substituted cyclopentanone was constructed via a[Rh(Duanphos)SbF6-catalyzed asymmetric enyne cycloisomerization and a copper hydride-mediated conjugate reduction.In addition,a new type of interphenylene prostaglandin scaffold was obtained via a formal Alder-ene reaction in high yield with excellent chemoselectivity.展开更多
Lignans have been established as a privileged scaffold in drug discovery,particularly in anticancer and antioxidant properties.Concise and efficient construction of lignans and their derivatives in a single operation ...Lignans have been established as a privileged scaffold in drug discovery,particularly in anticancer and antioxidant properties.Concise and efficient construction of lignans and their derivatives in a single operation holds great medicinal significance for structure-activity relationship studies yet remains challenging.Drawing inspiration from the biosynthesis of lignans,we present a general,high-step-economy palladium-catalyzed reaction that converts simple chemical feedstocks into dehydrodibenzylbutyrolactone lignans through the in-situ construction and coupling of two phenylpropanoid molecules.The diversity of organoboronic acids and the editability of enyne provide a powerful platform for the rapid construction of lignan libraries,featuring 82 lignans analogs,collective syntheses of 10 distinct lignan skeletons,and 13 hybrid molecules combining pharmacophore fragments with drug and derivatives.The subtle combination of phosphine ligands with quinones for switching chemoselectivity is vital to the success of this protocol.展开更多
The discovery of the novel reactivity of conjugated enynes,mediated by readily available halogenation reagents,opens a broad range of mechanistically unique pathways for the synthesis of highly functionalized chiral a...The discovery of the novel reactivity of conjugated enynes,mediated by readily available halogenation reagents,opens a broad range of mechanistically unique pathways for the synthesis of highly functionalized chiral allene derivatives.Bromoallenyl pyrrolidines can be synthesized via 1,4-addition of sulfonamide nitrogen nucleophiles and halogens to conjugated enynes.This process can lead to simultaneous formation of a highly functionalized axially chiral allene and a stereogenic center under economical and environmentally friendly reaction conditions.展开更多
Aryl sulfonyl radical triggered cascade cyclization of phenyl-linked 1,6-enynes for the synthesis of biologically important indenes containing alkenyl C—X bonds and 10a,11-dihydro-10H-benzo[b]fluorines is presented.I...Aryl sulfonyl radical triggered cascade cyclization of phenyl-linked 1,6-enynes for the synthesis of biologically important indenes containing alkenyl C—X bonds and 10a,11-dihydro-10H-benzo[b]fluorines is presented.In these radical cascade processes,three new chemical bonds,including C—S,C—C,and C—X bonds,and three C—C bonds are formed in one step.The method is attractive and valuable due to its metal-free,mild reaction conditions,broad substrate scope and good functional group tolerance.展开更多
An efficient and cost-effective method for the preparation of fluorinated conjugated enynes was described, tile method was compatible with a variety of functional groups such as chloride, amine, cyano and ester group....An efficient and cost-effective method for the preparation of fluorinated conjugated enynes was described, tile method was compatible with a variety of functional groups such as chloride, amine, cyano and ester group. The method could also be extended to the coupling of （R,Z）-3-（2-chloro-1,2-difluorovinyl）-4-alkyloxazolidin-2-one （3） with moderate yields.展开更多
Catalytic diastereodivergent hydrosilylative enyne cyclization with high generality and broad scope was achieved using electronic ac-tivated N-heterocyclic carbene-Ni(O)as a catalyst and R_(3)SiH as silane(IPr^(Cl),sy...Catalytic diastereodivergent hydrosilylative enyne cyclization with high generality and broad scope was achieved using electronic ac-tivated N-heterocyclic carbene-Ni(O)as a catalyst and R_(3)SiH as silane(IPr^(Cl),syn-:anti-selectivity from up to 98:2 to 7:93 by Z=0,NH vs.NMs,R^(1)=n-pentyl).Heterocycles bearing homoallylsilane rather than vinylsilane was obtained chemoselectively.The undesired yet highly competitive reactivity was suppressed,like direct hydrosilylation of alkene and alkyne concurrently.Optionally,the homoallylsilane products could be reduced further in one-pot using IPr^(Me) as ligand and(EtO)_(3)SiH as silane under otherwise the same standard condition as the above,offering practical access to additional stereocenters and more diverse product structures from enynes.展开更多
One of the largest subfamilies within the famous Daphniphyllum alkaloid family is made up of the yuzurimine-type(or macrodaphniphyllamine-type) alkaloids. Their complex aza-polycyclic caged structures, several contigu...One of the largest subfamilies within the famous Daphniphyllum alkaloid family is made up of the yuzurimine-type(or macrodaphniphyllamine-type) alkaloids. Their complex aza-polycyclic caged structures, several contiguous stereogenic centers, and vicinal all-carbon quaternary centers make these alkaloids formidable challenge for synthetic chemists. Recently, synthesis of these alkaloids has received extensive attention from our community. Herein, we wish to report the total synthesis of C_(14)–epideoxycalyciphylline H, a putative member of yuzurimine-type alkaloid subfamily. Key transformations employed in our approach include an intramolecular Prins reaction and a Pd-catalyzed enyne cycloisomerization. In addition, synthesis of a daphnezomine L-type alkaloid, paxdaphnidine A, was also studied.展开更多
Herein,copper-catalyzed 1,4-protosilylation and 1,4-protoborylation of enynic orthoesters have been developed.The enynic orthoesters as precursors of unstable enynic esters were applied to produce the functionalized 2...Herein,copper-catalyzed 1,4-protosilylation and 1,4-protoborylation of enynic orthoesters have been developed.The enynic orthoesters as precursors of unstable enynic esters were applied to produce the functionalized 2,3-allenoate products.Meanwhile,the asymmetric 1,4-protosilylation of enynic orthoesters with Ph Me2Si-Bpin was also studied.The chiral monopyridine imidazoline ligand was efficient to provide the asymmetric 1,4-protosilylation products with high enantioselectivity.展开更多
This study presents an efficient and innovative allylation strategy utilizing C/N/O nucleophilic reagents with attenuated reactivity,enabling the construction of versatile allyl compounds.The approach focuses on the s...This study presents an efficient and innovative allylation strategy utilizing C/N/O nucleophilic reagents with attenuated reactivity,enabling the construction of versatile allyl compounds.The approach focuses on the sequential allylation of dihalides in large-scale chemical manufacturing,effectively addressing the challenge of achieving selectivity in cascade reactions.The methodology is centered on the Cu-catalyzed C-olefination of alkynes with dihalides,significantly expediting the synthesis of a diverse array of finely conjugated enyne derivatives.Furthermore,a base-facilitated sequential condensation process has been developed to achieve the N-allylation of hydrazines,yielding a wide range of trisubstituted alkenyl hydrazones.Additionally,the protocol enables the synthesis of high-value ester compounds through O-allylation or esterification with dihalides.This transformation also facilitates the one-step synthesis of a variety of essential pharmaceuticals,demonstrating its broad synthetic utility and potential.展开更多
Comprehensive Summary:A practical photocatalytic annulation-biselenylation strategy has been developed for the efficient synthesis of biselenium-substituted 1-indanones(38 examples in total)with generally good yields(...Comprehensive Summary:A practical photocatalytic annulation-biselenylation strategy has been developed for the efficient synthesis of biselenium-substituted 1-indanones(38 examples in total)with generally good yields(up to 95%)and excellent stereoselectivity(>19:1 Z/E ratio)by employing enynones and diaryl selenides as starting materials under photosensitizer-free conditions.The reaction mechanism involves a cascade process comprising homolytic cleavage,radical addition,5-exo-dig cyclization,and radical capture,enabling sequential formation of multiple bonds,such as C(sp3)-Se,C(sp3)-C(sp2),and C(sp2)-Se bonds,to rapidly construct molecular complexity.Notably,this approach demonstrates wide substrate compatibility and excellent tolerability towards various functional groups.It is further characterized by its remarkable efficiency in creating chemical bonds and achieving high atomic utilization of 100%.展开更多
Palladium (II) catalyzed reactions of allyl propynoate in the presence of excess halide ions with or without allyl halide or acrolein were studied, yielding (E)-3-halo-2-allyl-acrylic acid as the sole product. A mecha...Palladium (II) catalyzed reactions of allyl propynoate in the presence of excess halide ions with or without allyl halide or acrolein were studied, yielding (E)-3-halo-2-allyl-acrylic acid as the sole product. A mechanism involving halopalladation, carbopalladation, ring opening and β-heteroatom elimination was proposed and was further justified by the reaction with deuterated substrate.展开更多
基金the National Natural Science Foundation of China(NSFC,No.22271241),Yunnan Key Laboratory of Chiral Functional Substance Research and Application(No.202402AN360010)Research Grants Council of Hong Kong(GRF,No.12303422)HKBU KRPS grant for financial support.
文摘The chemo-,regio-,and enantio-controlled synthesis of P-chiral phosphines in a general and efficient manner remains a significant synthetic challenge.In this study,a Pd-catalyzed hydrofunctionalization is developed for the highly selective synthesis of P-stereogenic alkenylphosphinates and alkenylphosphine oxides via conjugate addition of enynes.Notably,this methodology is suitable for both phosphine oxide and phosphinate nucleophiles,providing a versatile approach for the construction of diverse P-chiral organophosphosphorus compound.
基金support of this work by the funding of the National Natural Science Foundation of China(No.22371269)the State Key Laboratory of Elementoorganic Chemistry Nankai University(No.202001)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB0450301)the Open Project of Key Laboratory of Organosilicon Chemistry,and Material Technology of Ministry of Education,Hangzhou Normal University(No.KFJJ2022013)。
文摘Herein,we developed the first example of copper-catalyzed silicon radical-initiated 1,4-silylcyanation of unactivated 1,3-enynes,which provided an efficient method to access CN-bearing tri-and tetrasubstituted homoallenylsilane derivatives in high yields with excellent regioselectivities.This protocol featured good functional group compatibility and broad substrate scopes,enabling the formation of C-Si bond under cheap copper catalyst with a low loading.Furthermore,this means showed potential application value in the late-stage functionalization of natural products.
基金supported by the National Natural Science Foundation of China (Nos. 21822303 21772020 22173083)Program for Science Technology Innovation Talents in Universities of Henan Province (No. 20HASTIT004)the support from the Henan Province Supercomputing Center
文摘Hybrid quantum mechanics/molecular mechanics calculations were performed to elucidate how[Mn^(Ⅲ)porphyrin]^(+X−)-based metal-organic frameworks(MOFs)catalyze the[2+1]cycloisomerization of enynes and why zwitterionic MOFs exhibit strong activity in Lewis acid catalysis.The calculations showed that zwitterionic MOFs have a“pure cationic active center”leading to a concerted nucleophilic attack pathway with lower barriers.In contrast,metals with coordinating anions have reduced electrophilicity,resulting in a stepwise radical-type pathway with much higher barriers.Further calculations showed the nature of catalysis was strongly depended on the charge on the anion ligand.A good linear relationship between the NPA charge and barrier was found,and verified by 73 anions with small derivations,which presents a universal adaptive character for various coordinated anions.
文摘Polyhydroxy enyne compound （＋）-（1＇S, 2R, 3S, 5S, 6S）-5,6-dimethoxy-5, 6-dimethyl- 2-（1＇-hydroxylpropyl-2-ne）-3-vinyl-l,4-dioxane has been synthesized from D-（-）-tartaric acid. A new chiral center was established by nucleophilic addition with 87% de. The modified Mosher＇s method was employed to confirm the absolute configuration of 17, which assigned the S-configuration at the new chiral center.
基金Financial support from Dalian Outstanding Young Scientific Talent(No.2020RJ05)the National Natural Science Foundation of China(Nos.22071239,21971234)。
文摘A regiodivergent hydrophosphorylation of enynes with phosphites has been developed using earthabundant nickel catalyst.The manipulation of regioselectivity can be achieved by regulating the insertion order of alkyne bonds with(RO)_(2)P(O)-Ni-H or R_(2)P(O)O-Ni-H species,respectively.Under the Ni/Xantphos catalysis,4,1-hydrophosphorylation is selectively obtained while the adding of acid can promote reactions towards 1,2-addition.By employing an additional Pd-H catalysis,2,1-hydrophosphorylation is also an accessible task in one-pot reaction.Mechanistic studies and analysis have also been performed to interpret the origin of the regioselective regulation.This work highlights the arts in accessing different regioisomers by diverting common elementary reaction steps.
基金the National Key R&D Program of China(No.2021YFA1500201)Shenzhen Science and Technology Innovation Committee(No.KQTD20150717103157174)+8 种基金Stable Support Plan Program of Shenzhen Natural Science Fund(No.20200925161222002)Key-Area Research and Development Program of Guangdong Province(No.2020B010188001)Innovative Team of Universities in Guangdong Province(No.2020KCXTD016)High Level of Special Funds(G03050K003)National Natural Science Foundation of China(No.21991113)the National Natural Science Foundation of China(Nos.21901107 and 22171129)Guangdong Innovative Program(2019BT02Y335)the Guangdong Basic and Applied Basic Research Foundation(2022B1515020055)Shenzhen Science and Technology Innovation Committee(No.JCYJ20210324104202007)for financial support.
文摘Herein,a highly enantioselective formal synthesis of(+)-Treprostinil via the interphenylene prostaglandin E1 scaffold was described.The chiral multi-substituted cyclopentanone was constructed via a[Rh(Duanphos)SbF6-catalyzed asymmetric enyne cycloisomerization and a copper hydride-mediated conjugate reduction.In addition,a new type of interphenylene prostaglandin scaffold was obtained via a formal Alder-ene reaction in high yield with excellent chemoselectivity.
基金Financial support was provided by the State Key Laboratory of Pulp and Paper Engineering(No.2022PY01)the National Natural Science Foundation of China(Nos.22231002 and 21871095)the Key-Area Research and Development Program of Guangdong Province(No.2020B010188001)。
文摘Lignans have been established as a privileged scaffold in drug discovery,particularly in anticancer and antioxidant properties.Concise and efficient construction of lignans and their derivatives in a single operation holds great medicinal significance for structure-activity relationship studies yet remains challenging.Drawing inspiration from the biosynthesis of lignans,we present a general,high-step-economy palladium-catalyzed reaction that converts simple chemical feedstocks into dehydrodibenzylbutyrolactone lignans through the in-situ construction and coupling of two phenylpropanoid molecules.The diversity of organoboronic acids and the editability of enyne provide a powerful platform for the rapid construction of lignan libraries,featuring 82 lignans analogs,collective syntheses of 10 distinct lignan skeletons,and 13 hybrid molecules combining pharmacophore fragments with drug and derivatives.The subtle combination of phosphine ligands with quinones for switching chemoselectivity is vital to the success of this protocol.
基金the University of Wisconsin-Madison and the American Chemical Society Petroleum Research Fund (48092-G) for funding
文摘The discovery of the novel reactivity of conjugated enynes,mediated by readily available halogenation reagents,opens a broad range of mechanistically unique pathways for the synthesis of highly functionalized chiral allene derivatives.Bromoallenyl pyrrolidines can be synthesized via 1,4-addition of sulfonamide nitrogen nucleophiles and halogens to conjugated enynes.This process can lead to simultaneous formation of a highly functionalized axially chiral allene and a stereogenic center under economical and environmentally friendly reaction conditions.
基金the National Natural Science Foundation of China(No.21861043)the Yunnan Fundamental Research Projects(No.2019FB016)Scientific and Technological Innovation Team of Optical Functional Materials of Yunnan Provincial Education Department forfinancial support.
文摘Aryl sulfonyl radical triggered cascade cyclization of phenyl-linked 1,6-enynes for the synthesis of biologically important indenes containing alkenyl C—X bonds and 10a,11-dihydro-10H-benzo[b]fluorines is presented.In these radical cascade processes,three new chemical bonds,including C—S,C—C,and C—X bonds,and three C—C bonds are formed in one step.The method is attractive and valuable due to its metal-free,mild reaction conditions,broad substrate scope and good functional group tolerance.
基金Acknowledgement The authors gratefully acknowledge the financial support from National Basic Research Program of China （Nos. 2012CB821600, 2010CB126103）, the Key Program of Natural Science Foundation of China （No.21032006）, National Natural Science Foundation of China （Nos. 21172245, 21172244, B020304）, Agroscientific Research in the Public Interest （No. 201103007）, the National Key Technologies R＆D Program （No. 2011BAE06B05）, Shanghai Scientific Research Program （No. 10XD1405200）, and SIOC.
文摘An efficient and cost-effective method for the preparation of fluorinated conjugated enynes was described, tile method was compatible with a variety of functional groups such as chloride, amine, cyano and ester group. The method could also be extended to the coupling of （R,Z）-3-（2-chloro-1,2-difluorovinyl）-4-alkyloxazolidin-2-one （3） with moderate yields.
基金the Guangdong Provincial Key Laboratory of Catalysis(No.2020B121201002)NSFC(No.22071096)SUSTech(Nos.Y01501808 and Y01506014).
文摘Catalytic diastereodivergent hydrosilylative enyne cyclization with high generality and broad scope was achieved using electronic ac-tivated N-heterocyclic carbene-Ni(O)as a catalyst and R_(3)SiH as silane(IPr^(Cl),syn-:anti-selectivity from up to 98:2 to 7:93 by Z=0,NH vs.NMs,R^(1)=n-pentyl).Heterocycles bearing homoallylsilane rather than vinylsilane was obtained chemoselectively.The undesired yet highly competitive reactivity was suppressed,like direct hydrosilylation of alkene and alkyne concurrently.Optionally,the homoallylsilane products could be reduced further in one-pot using IPr^(Me) as ligand and(EtO)_(3)SiH as silane under otherwise the same standard condition as the above,offering practical access to additional stereocenters and more diverse product structures from enynes.
基金the National Natural Science Foundation of China (Nos.21971104 and 22271136)Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis (No.ZDSYS20190902093215877)+4 种基金Guangdong Provincial Key Laboratory of Catalysis (No.2020B121201002)Guangdong Innovative Program (No.2019BT02Y335)Education Department of Guangdong Province, Key research projects in colleges and universities in Guangdong Province (No.2021ZDZX2035)Shenzhen Nobel Prize Scientists Laboratory Project (No.C17783101)Innovative Team of Universities in Guangdong Province (No.2020KCXTD016)。
文摘One of the largest subfamilies within the famous Daphniphyllum alkaloid family is made up of the yuzurimine-type(or macrodaphniphyllamine-type) alkaloids. Their complex aza-polycyclic caged structures, several contiguous stereogenic centers, and vicinal all-carbon quaternary centers make these alkaloids formidable challenge for synthetic chemists. Recently, synthesis of these alkaloids has received extensive attention from our community. Herein, we wish to report the total synthesis of C_(14)–epideoxycalyciphylline H, a putative member of yuzurimine-type alkaloid subfamily. Key transformations employed in our approach include an intramolecular Prins reaction and a Pd-catalyzed enyne cycloisomerization. In addition, synthesis of a daphnezomine L-type alkaloid, paxdaphnidine A, was also studied.
基金the funding support of the National Natural Science Foundation of China(No.21871240)the Strategic Priority Research Program of the CAS(No.XDPB14)the Fundamental Research Funds for the Central Universities(No.WK2060190082)。
文摘Herein,copper-catalyzed 1,4-protosilylation and 1,4-protoborylation of enynic orthoesters have been developed.The enynic orthoesters as precursors of unstable enynic esters were applied to produce the functionalized 2,3-allenoate products.Meanwhile,the asymmetric 1,4-protosilylation of enynic orthoesters with Ph Me2Si-Bpin was also studied.The chiral monopyridine imidazoline ligand was efficient to provide the asymmetric 1,4-protosilylation products with high enantioselectivity.
基金grateful to the Hundred-Talent Program of the Chinese Academy of Sciences(YBR2025002)the Key project of International Cooperation Bureau,CAS(040GJHZ2024013MI)+1 种基金the Natural Science Foundation of Shanxi Province of China(202303021221256)the Research Project Supported by Shanxi Scholarship Council of China and the State Key Laboratory of Coal Conversion,Institute of Coal Chemistry,CAS(2024KJT003).
文摘This study presents an efficient and innovative allylation strategy utilizing C/N/O nucleophilic reagents with attenuated reactivity,enabling the construction of versatile allyl compounds.The approach focuses on the sequential allylation of dihalides in large-scale chemical manufacturing,effectively addressing the challenge of achieving selectivity in cascade reactions.The methodology is centered on the Cu-catalyzed C-olefination of alkynes with dihalides,significantly expediting the synthesis of a diverse array of finely conjugated enyne derivatives.Furthermore,a base-facilitated sequential condensation process has been developed to achieve the N-allylation of hydrazines,yielding a wide range of trisubstituted alkenyl hydrazones.Additionally,the protocol enables the synthesis of high-value ester compounds through O-allylation or esterification with dihalides.This transformation also facilitates the one-step synthesis of a variety of essential pharmaceuticals,demonstrating its broad synthetic utility and potential.
文摘Comprehensive Summary:A practical photocatalytic annulation-biselenylation strategy has been developed for the efficient synthesis of biselenium-substituted 1-indanones(38 examples in total)with generally good yields(up to 95%)and excellent stereoselectivity(>19:1 Z/E ratio)by employing enynones and diaryl selenides as starting materials under photosensitizer-free conditions.The reaction mechanism involves a cascade process comprising homolytic cleavage,radical addition,5-exo-dig cyclization,and radical capture,enabling sequential formation of multiple bonds,such as C(sp3)-Se,C(sp3)-C(sp2),and C(sp2)-Se bonds,to rapidly construct molecular complexity.Notably,this approach demonstrates wide substrate compatibility and excellent tolerability towards various functional groups.It is further characterized by its remarkable efficiency in creating chemical bonds and achieving high atomic utilization of 100%.
基金theMajorStateBasicResearchDevelopmentProgramofChina (No .G2 0 0 0 0 775 0 2 A) ,andtheNationalNaturalScienceFoundationofChina (No.2 0 0 72 0 45 )
文摘Palladium (II) catalyzed reactions of allyl propynoate in the presence of excess halide ions with or without allyl halide or acrolein were studied, yielding (E)-3-halo-2-allyl-acrylic acid as the sole product. A mechanism involving halopalladation, carbopalladation, ring opening and β-heteroatom elimination was proposed and was further justified by the reaction with deuterated substrate.
