The development of highly active and enantioselective ligands and catalysts for the asymmetric hydrogenation of ketone has been the goal of synthetic chemists for more than fifty years.Herein,a series of ferrocene-bas...The development of highly active and enantioselective ligands and catalysts for the asymmetric hydrogenation of ketone has been the goal of synthetic chemists for more than fifty years.Herein,a series of ferrocene-based tetradentate ligands were developed and applied in Ir-catalysed asymmetric hydrogenation of ketone.The hydrolytic ring-opening of the oxazoline moiety of ligand f-amphox leads to the accidental discovery of a highly efficient and enantioselective tetradentate ligand f-phamidol which showed extraordinarily high reactivity and enantioselectivity(up to 99%yield,up to>99%ee and up to 1,000,000 TON).In addition,two types of other tetradentate ligands f-phamida and f-phamide were also synthesized and evaluated.展开更多
In this work, it is found that 1,8-dihydroxyimino-1,2,7,8-tetraphenyl-3,6-diazocta-2,6-diene(PhdoenH2) could react with nickel(Ⅱ) salt to yield a mononickel complex Ni(Phdoen)(1) with unusual [2N2O]-coordinated mode,...In this work, it is found that 1,8-dihydroxyimino-1,2,7,8-tetraphenyl-3,6-diazocta-2,6-diene(PhdoenH2) could react with nickel(Ⅱ) salt to yield a mononickel complex Ni(Phdoen)(1) with unusual [2N2O]-coordinated mode, while the analogous diimine-dioxime ligands usually form the [4N]-coordinated mode. The novel complex 1 has been carefully characterized by 1H NMR, elemental analysis, and X-ray diffraction structure analysis. The influences of the coordination modes on the structures and redox properties have been further investigated. Theoretical investigations revealed that the different coordination modes were ascribed to the thermodynamic properties of ligands.展开更多
A new class of iron（II） hydrides based on a tetradentate PSNP ligand were synthesized and fully characterized. All the iron（II） complexes feature a folded PSNP ligand with cis reactive sites. The hydrido iron comp...A new class of iron（II） hydrides based on a tetradentate PSNP ligand were synthesized and fully characterized. All the iron（II） complexes feature a folded PSNP ligand with cis reactive sites. The hydrido iron complex [2 H（NCMe[2_TD$IF]1）]（BF4） is capable of catalyzing aldehyde hydroboration by pinacolborane（HBpin） and with extremely high efficiency at room temperature. Aldehydes with various functional groups are compatible.展开更多
A novel hydrido iridium chloride complex supported by a tetradentate PNCP ligand has been synthesized and characterized. Upon activation with NaOtBu, the PNCP-IrHC1 complex is active for transfer dehydrogenation of cy...A novel hydrido iridium chloride complex supported by a tetradentate PNCP ligand has been synthesized and characterized. Upon activation with NaOtBu, the PNCP-IrHC1 complex is active for transfer dehydrogenation of cyclic and linear alkanes.展开更多
Enantioselective cis-dihydroxylation of alkenes represents an ideal route to synthesize enantioenriched syn-2,3-dihydroxy esters that are important structural motifs in numerous biologically and pharmaceutically relev...Enantioselective cis-dihydroxylation of alkenes represents an ideal route to synthesize enantioenriched syn-2,3-dihydroxy esters that are important structural motifs in numerous biologically and pharmaceutically relevant molecules.Bioinspired nonheme iron-catalyzed enantioselective cis-dihydroxylation meets the requirement of the modern synthetic chemistry from the atomic economy,green chemistry,and sustainable development perspectives.However,nonheme iron-catalyzed enantioselective cis-dihydroxylation is much underdeveloped because of the formidable challenges of controlling chemo-and enantioselectivities and product selectivity caused by the competitive epoxidation,cis-dihydroxylation,and overoxidation reactions.Herein,we disclose the fabrication of a biologically inspired nonheme iron complex-catalyzed enantioselective cis-dihydroxylation of multisubstituted acrylates using hydrogen peroxide(H_(2)O_(2))as the terminal oxidant by controlling the non-ligating or weakly ligating counterions of iron(Ⅱ)complexes,demonstrating a dramatic counteranion effect on the enantioselective cisdihydroxylation of olefins by H_(2)O_(2) catalyzed by nonheme iron complexes.A range of structurally disparate alkenes were transformed to the corresponding syn-2,3-dihydroxy esters in practically useful yields with exquisite chemo-and enantioselectivities(up to 99% ee).Given the mild and benign nature of this biologically inspired oxidation system as well as the ubiquity and synthetic utility of enantioenriched syn-2,3-dihydroxy esters as pharmaceuticals candidates and natural products,we expect that this strategy could serve as a promising complement to the well-known Sharpless asymmetric dihydroxylation,which is the chemical reaction of an alkene with OsO_(4) to produce a vicinal diol.展开更多
基金X.Zhang is indebted to the National Key R&D Program of China(No.2021YFA1500201)the Shenzhen Science and Technology Innovation Committee(SSTIC)(No.KQTD2015071710315717)+5 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)National Natural Science Foundation of China(No.21991113)G.Q.Chen gratefully acknowledges the National Natural Science Foundation of China(Nos.21901107 and 22171129)SSTIC(No.JCYJ20210324104202007)for financial support.
文摘The development of highly active and enantioselective ligands and catalysts for the asymmetric hydrogenation of ketone has been the goal of synthetic chemists for more than fifty years.Herein,a series of ferrocene-based tetradentate ligands were developed and applied in Ir-catalysed asymmetric hydrogenation of ketone.The hydrolytic ring-opening of the oxazoline moiety of ligand f-amphox leads to the accidental discovery of a highly efficient and enantioselective tetradentate ligand f-phamidol which showed extraordinarily high reactivity and enantioselectivity(up to 99%yield,up to>99%ee and up to 1,000,000 TON).In addition,two types of other tetradentate ligands f-phamida and f-phamide were also synthesized and evaluated.
基金the Natural Science Foundation of China(21773184 and 21671158)。
文摘In this work, it is found that 1,8-dihydroxyimino-1,2,7,8-tetraphenyl-3,6-diazocta-2,6-diene(PhdoenH2) could react with nickel(Ⅱ) salt to yield a mononickel complex Ni(Phdoen)(1) with unusual [2N2O]-coordinated mode, while the analogous diimine-dioxime ligands usually form the [4N]-coordinated mode. The novel complex 1 has been carefully characterized by 1H NMR, elemental analysis, and X-ray diffraction structure analysis. The influences of the coordination modes on the structures and redox properties have been further investigated. Theoretical investigations revealed that the different coordination modes were ascribed to the thermodynamic properties of ligands.
基金financial support from the "1000 Youth Talents Plan"the National Natural Science Foundation of China (Nos. 21402107, 91427303)the Natural Science Foundation of Shandong Province (Nos. ZR2014M011)
文摘A new class of iron（II） hydrides based on a tetradentate PSNP ligand were synthesized and fully characterized. All the iron（II） complexes feature a folded PSNP ligand with cis reactive sites. The hydrido iron complex [2 H（NCMe[2_TD$IF]1）]（BF4） is capable of catalyzing aldehyde hydroboration by pinacolborane（HBpin） and with extremely high efficiency at room temperature. Aldehydes with various functional groups are compatible.
基金financially supported by the National Basic Research Program of China(2015CB856600)the National Natural Science Foundation of China(21422209,21432011,21421091)
文摘A novel hydrido iridium chloride complex supported by a tetradentate PNCP ligand has been synthesized and characterized. Upon activation with NaOtBu, the PNCP-IrHC1 complex is active for transfer dehydrogenation of cyclic and linear alkanes.
基金the National Natural Science Foundation of China(no.21771087 to B.W and no.21703080 to J.C)the NSF of Shandong Province(no.ZR2020YQ10 to B.W)+1 种基金Taishan Scholar Program of Shandong Province(no.tsqn201812078 to B.W.)the NRF of Korea(no.NRF-2021R1A3B1076539 to W.N.and no.NRF-2020R1I1A1A01074630 to Y.-M.L.).
文摘Enantioselective cis-dihydroxylation of alkenes represents an ideal route to synthesize enantioenriched syn-2,3-dihydroxy esters that are important structural motifs in numerous biologically and pharmaceutically relevant molecules.Bioinspired nonheme iron-catalyzed enantioselective cis-dihydroxylation meets the requirement of the modern synthetic chemistry from the atomic economy,green chemistry,and sustainable development perspectives.However,nonheme iron-catalyzed enantioselective cis-dihydroxylation is much underdeveloped because of the formidable challenges of controlling chemo-and enantioselectivities and product selectivity caused by the competitive epoxidation,cis-dihydroxylation,and overoxidation reactions.Herein,we disclose the fabrication of a biologically inspired nonheme iron complex-catalyzed enantioselective cis-dihydroxylation of multisubstituted acrylates using hydrogen peroxide(H_(2)O_(2))as the terminal oxidant by controlling the non-ligating or weakly ligating counterions of iron(Ⅱ)complexes,demonstrating a dramatic counteranion effect on the enantioselective cisdihydroxylation of olefins by H_(2)O_(2) catalyzed by nonheme iron complexes.A range of structurally disparate alkenes were transformed to the corresponding syn-2,3-dihydroxy esters in practically useful yields with exquisite chemo-and enantioselectivities(up to 99% ee).Given the mild and benign nature of this biologically inspired oxidation system as well as the ubiquity and synthetic utility of enantioenriched syn-2,3-dihydroxy esters as pharmaceuticals candidates and natural products,we expect that this strategy could serve as a promising complement to the well-known Sharpless asymmetric dihydroxylation,which is the chemical reaction of an alkene with OsO_(4) to produce a vicinal diol.
