The rational design of efficient single-atomic(SA)catalysts is essential and highly desirable but impeded by the lack of sufficient acknowledge between structure and property.To this end,it is critical to clarify the ...The rational design of efficient single-atomic(SA)catalysts is essential and highly desirable but impeded by the lack of sufficient acknowledge between structure and property.To this end,it is critical to clarify the effect of the coordination structure of active metal centers on the catalytic activities for the design of such catalysts.Here,we report that different coordination structures of SA Pt catalysts can dramatically influence their activities for anti-Markovnikov hydroboration of alkenes.Compared with the other two coordination structures(Pt-N4 and Pt-O2),the SA Pt species coordinated with three O atoms(Pt-O3)display the highest turnover number value of 3288 for the hydroboration reaction to access the important alkylboronic esters.Density functional theory calculations reveal that a superior catalytic activity can be expected for alkene hydroboration over the three O coordinated Pt species due to the lowest reaction energy(ΔG)limiting step from the reaction phase diagram.展开更多
The sex pheromone of grapholitha molesta 8(Z/E)-dodecen-1-ol acetate (6) was synthesized by using oleic acids as the raw material. 1,8(Z)-Heptadecadiene (2) was obtained from the decarbonylation reaction of oleic acid...The sex pheromone of grapholitha molesta 8(Z/E)-dodecen-1-ol acetate (6) was synthesized by using oleic acids as the raw material. 1,8(Z)-Heptadecadiene (2) was obtained from the decarbonylation reaction of oleic acid (1) in the presence of palladium complexes catalyst. Selective hydroboration and oxidation of 2 by Ca(BH 4) 2/H 2O 2 system gave 8(Z)-heptadecen-1-ol (3), which then was acetylized by treatment with Ac 2O/pyridine to afford 8(Z)-heptadecen-ol acetate(4). The compound 4 was ozonized to form the key intermediate 8-acetoxyoctanal (5), then compound 5 was coupled with the Wittig regents to obtain the title compound 8(Z/E)dodecen-1-ol acetate (6), Z/E molar ratio is 25∶75. The overall yield was 45%. The structures of all the compounds were confirmed by IR, MS and NMR spectra.展开更多
Selective reduction of readily available N-heteroarenes is important in both organic synthesis and chemical biology.Herein,we describe ligand-controlled regiodivergent hydroboration of quinolines using well-defined am...Selective reduction of readily available N-heteroarenes is important in both organic synthesis and chemical biology.Herein,we describe ligand-controlled regiodivergent hydroboration of quinolines using well-defined amido-manganese catalysts,with an emphasis on the rarely reported 1,4-regioselectivity.Mechanistic studies showed that 1,2-hydroboration of quinoline was kinetically favorable and reversible,whereas 1,4-hydroboration was under thermodynamic control.Using a 1-methyimidazolebased pincer amido-manganese complex as the catalyst,cooperative C-H…N andπ…πnoncovalent interactions between the 1-methyimidazole moiety and quinoline substrates enabled kinetic accessibility of 1,4-hydroboration,giving thermodynamically favored 1,4-hydroborated quinolines as the major products.On this basis,Mn-catalyzed 1,4-hydroboration of a series of substituted quinolines proceeded smoothly in high yields.A high turnover number of 2500 was achieved in this reaction with satisfying regioselectivity.This transformation could be further applied to the C3-selective functionalization of quinolines,highlighting the synthetic utility of this methodology.In contrast,using a pyridine-based pincer amido-manganese complex as the catalyst,which lacked the C-H…N interaction,the free-energy barrier for 1,4-hydroboration significantly increased through a N-B…N interaction between the“HMn-NB”species and quinoline,resulting in the kinetically favored 1,2-hydroboration product with excellent regioselectivity.展开更多
The planar-chiral ligands have been widely applied as a class of unique and significant ligands in asymmetric catalysis.Among them,chiral[2.2]paracycyclophane has emerged as a privileged type of planar-chiral framewor...The planar-chiral ligands have been widely applied as a class of unique and significant ligands in asymmetric catalysis.Among them,chiral[2.2]paracycyclophane has emerged as a privileged type of planar-chiral framework and has been utilized as an important toolbox due to their structural stability.Herein,we design and synthesize[2.2]paracyclophane-derived oxazole-pyrimidine ligands(abberviated as PYMCOX).These N,N-ligands with stable properties,rigid structure and large steric hindrance performed successfully in nickel-catalyzed asymmetric 1,2-reduction ofα,β-unsaturated ketones,affording the chiral allylic alcohols with up to 99%yield and 99%ee.Meanwhile,this reduction reaction could be conducted on gram-scale without loss of activity and enantioselectivity,and the chiral ligand could be conveniently recovered with high yield.展开更多
We report two air-stable nickel(II) half-sandwich complexes,Cp*Ni(1,2-Cy_(2)PC_(6)H_(4)O)(1) and Cp*Ni(1,2-Ph_(2)PC_(6)H4NH)(2),for cooperative B-H bond activation and their applications in catalytic hydroboration of ...We report two air-stable nickel(II) half-sandwich complexes,Cp*Ni(1,2-Cy_(2)PC_(6)H_(4)O)(1) and Cp*Ni(1,2-Ph_(2)PC_(6)H4NH)(2),for cooperative B-H bond activation and their applications in catalytic hydroboration of unsaturated organic compounds.Both 1 and 2 react with HBpin by adding the B-H bond across the Ni-X bond (X=O or N),giving rise to the 18-electron Ni(II)-H active species,[H1(Bpin)]and[H_(2)(Bpin)].Subtle tuning of the Ni-X pair and the supporting ancillary phosphine have a significant effect on the reactivity and catalytic performance of Cp*Ni(1,2-R_(2)PC_(6)H_(4)X).Unlike[H_(2)(Bpin)],the activation of HBpin in[H1(Bpin)]is reversible,which enables the Ni-O complex to be an effective cooperative catalyst in the hydroboration of N-heteroarenes,and as well as ketones and imines.展开更多
Regiodivergent 1,2-hydroboration of 1,3-dienes with pinacolborane has been accomplished by well-defined cobalt complexes of different bidentate ligands. The iminopyridine-cobalt system is selective for Markovnikov 1,2...Regiodivergent 1,2-hydroboration of 1,3-dienes with pinacolborane has been accomplished by well-defined cobalt complexes of different bidentate ligands. The iminopyridine-cobalt system is selective for Markovnikov 1,2-hydroboration to form allylboronates, while the FOXAP-cobalt(FOXAP=(S)-1-(diphenylphosphino)-2-[(S)-4-isopropyloxazolin-2-yl]ferrocene) catalyst effects the complementary anti-Markonikv 1,2-hydroboration to afford homoallyboronates with high regioselectivity.展开更多
An efficient copper-catalyzed decarboxylative hydroboration of phenylpropiolic acids with bis（pinacolato）diboron was developed, affording b-vinylboronates as the only products in high yields. Extra hydrogen sources ...An efficient copper-catalyzed decarboxylative hydroboration of phenylpropiolic acids with bis（pinacolato）diboron was developed, affording b-vinylboronates as the only products in high yields. Extra hydrogen sources such as methanol are not needed in this catalytic system. This reaction could be performed successfully under ligand- and base-free conditions. It demonstrated that phenylpropiolic acids can be employed as alkyne synthons in the hydroboration reaction and exhibited good reactivity and higher selectivity than terminal alkynes.展开更多
基金This work was supported by the National Key R&D Program of China(2018YFA0702003)the National Natural Science Foundation of China(21890383,21671117,21871159 and 21901135).
文摘The rational design of efficient single-atomic(SA)catalysts is essential and highly desirable but impeded by the lack of sufficient acknowledge between structure and property.To this end,it is critical to clarify the effect of the coordination structure of active metal centers on the catalytic activities for the design of such catalysts.Here,we report that different coordination structures of SA Pt catalysts can dramatically influence their activities for anti-Markovnikov hydroboration of alkenes.Compared with the other two coordination structures(Pt-N4 and Pt-O2),the SA Pt species coordinated with three O atoms(Pt-O3)display the highest turnover number value of 3288 for the hydroboration reaction to access the important alkylboronic esters.Density functional theory calculations reveal that a superior catalytic activity can be expected for alkene hydroboration over the three O coordinated Pt species due to the lowest reaction energy(ΔG)limiting step from the reaction phase diagram.
文摘The sex pheromone of grapholitha molesta 8(Z/E)-dodecen-1-ol acetate (6) was synthesized by using oleic acids as the raw material. 1,8(Z)-Heptadecadiene (2) was obtained from the decarbonylation reaction of oleic acid (1) in the presence of palladium complexes catalyst. Selective hydroboration and oxidation of 2 by Ca(BH 4) 2/H 2O 2 system gave 8(Z)-heptadecen-1-ol (3), which then was acetylized by treatment with Ac 2O/pyridine to afford 8(Z)-heptadecen-ol acetate(4). The compound 4 was ozonized to form the key intermediate 8-acetoxyoctanal (5), then compound 5 was coupled with the Wittig regents to obtain the title compound 8(Z/E)dodecen-1-ol acetate (6), Z/E molar ratio is 25∶75. The overall yield was 45%. The structures of all the compounds were confirmed by IR, MS and NMR spectra.
基金the National Key R&D Program of China(grant no.2021YFF0701600)the National Natural Science Foundation of China(grant no.22225103)Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs,Shanghai Jiao Tong University,and the China Postdoctoral Science Foundation(grant nos.2020M680021 and 2021T140366),which was greatly appreciated.
文摘Selective reduction of readily available N-heteroarenes is important in both organic synthesis and chemical biology.Herein,we describe ligand-controlled regiodivergent hydroboration of quinolines using well-defined amido-manganese catalysts,with an emphasis on the rarely reported 1,4-regioselectivity.Mechanistic studies showed that 1,2-hydroboration of quinoline was kinetically favorable and reversible,whereas 1,4-hydroboration was under thermodynamic control.Using a 1-methyimidazolebased pincer amido-manganese complex as the catalyst,cooperative C-H…N andπ…πnoncovalent interactions between the 1-methyimidazole moiety and quinoline substrates enabled kinetic accessibility of 1,4-hydroboration,giving thermodynamically favored 1,4-hydroborated quinolines as the major products.On this basis,Mn-catalyzed 1,4-hydroboration of a series of substituted quinolines proceeded smoothly in high yields.A high turnover number of 2500 was achieved in this reaction with satisfying regioselectivity.This transformation could be further applied to the C3-selective functionalization of quinolines,highlighting the synthetic utility of this methodology.In contrast,using a pyridine-based pincer amido-manganese complex as the catalyst,which lacked the C-H…N interaction,the free-energy barrier for 1,4-hydroboration significantly increased through a N-B…N interaction between the“HMn-NB”species and quinoline,resulting in the kinetically favored 1,2-hydroboration product with excellent regioselectivity.
基金Financial support from National Natural Science Foundation of China (22171260)K.C.Wong Education Foundation of CAS (GJTD-2020-08)is acknowledged.
文摘The planar-chiral ligands have been widely applied as a class of unique and significant ligands in asymmetric catalysis.Among them,chiral[2.2]paracycyclophane has emerged as a privileged type of planar-chiral framework and has been utilized as an important toolbox due to their structural stability.Herein,we design and synthesize[2.2]paracyclophane-derived oxazole-pyrimidine ligands(abberviated as PYMCOX).These N,N-ligands with stable properties,rigid structure and large steric hindrance performed successfully in nickel-catalyzed asymmetric 1,2-reduction ofα,β-unsaturated ketones,affording the chiral allylic alcohols with up to 99%yield and 99%ee.Meanwhile,this reduction reaction could be conducted on gram-scale without loss of activity and enantioselectivity,and the chiral ligand could be conveniently recovered with high yield.
基金the financial support from the National Natural Science Foundation of China (Nos. 22022102 and 22071010)the financial support from China Postdoctoral Science Foundation (No. 2021M700462)。
文摘We report two air-stable nickel(II) half-sandwich complexes,Cp*Ni(1,2-Cy_(2)PC_(6)H_(4)O)(1) and Cp*Ni(1,2-Ph_(2)PC_(6)H4NH)(2),for cooperative B-H bond activation and their applications in catalytic hydroboration of unsaturated organic compounds.Both 1 and 2 react with HBpin by adding the B-H bond across the Ni-X bond (X=O or N),giving rise to the 18-electron Ni(II)-H active species,[H1(Bpin)]and[H_(2)(Bpin)].Subtle tuning of the Ni-X pair and the supporting ancillary phosphine have a significant effect on the reactivity and catalytic performance of Cp*Ni(1,2-R_(2)PC_(6)H_(4)X).Unlike[H_(2)(Bpin)],the activation of HBpin in[H1(Bpin)]is reversible,which enables the Ni-O complex to be an effective cooperative catalyst in the hydroboration of N-heteroarenes,and as well as ketones and imines.
基金supported by the National Key R&D Program of China (2016YFA0202900, 2015CB856600)the National Natural Science Foundation of China (21825109, 21432011, 21572255, 21732006)+1 种基金Chinese Academy of Sciences (XDB20000000, QYZDB-SSWSLH016)Science and Technology Commission Shanghai Municipality (17JC1401200)
文摘Regiodivergent 1,2-hydroboration of 1,3-dienes with pinacolborane has been accomplished by well-defined cobalt complexes of different bidentate ligands. The iminopyridine-cobalt system is selective for Markovnikov 1,2-hydroboration to form allylboronates, while the FOXAP-cobalt(FOXAP=(S)-1-(diphenylphosphino)-2-[(S)-4-isopropyloxazolin-2-yl]ferrocene) catalyst effects the complementary anti-Markonikv 1,2-hydroboration to afford homoallyboronates with high regioselectivity.
基金Financial support from the National Science Foundation of China (No. 21202049)the Recruitment Program of Global Experts (1000 Talents Plan)+2 种基金Fujian Hundred Talents PlanProgram of Innovative Research Team of Huaqiao UniversityInstrumental Analysis Center of Huaqiao University for analysis support
文摘An efficient copper-catalyzed decarboxylative hydroboration of phenylpropiolic acids with bis（pinacolato）diboron was developed, affording b-vinylboronates as the only products in high yields. Extra hydrogen sources such as methanol are not needed in this catalytic system. This reaction could be performed successfully under ligand- and base-free conditions. It demonstrated that phenylpropiolic acids can be employed as alkyne synthons in the hydroboration reaction and exhibited good reactivity and higher selectivity than terminal alkynes.
