A novel process for sulfidation of ZnO by co-grinding with sulfur and reductive additives （P, Fe, A1, and Mg） was developed. The sulfidation extent of ZnO with the addition of P, Fe, A1 or Mg can reach 85.2%, 81.6%,...A novel process for sulfidation of ZnO by co-grinding with sulfur and reductive additives （P, Fe, A1, and Mg） was developed. The sulfidation extent of ZnO with the addition of P, Fe, A1 or Mg can reach 85.2%, 81.6%, 96.7% and 92.6% after grinding for 4, 6, 1 and 1 h, respectively. Based on the chemical phase composition analysis and morphological characteristics of sulfidized products by XRD, SEM and TEM, a possible reaction mechanism, mechanically induced self-propagating reaction （MSR）, was proposed to explain the sulfidization reaction. In addition, the floatability of sulfidized products was investigated for the recovery of metal sulfide and ZnS can be concentrated with a high concentration ratio and concentrate grade. By using the sulfidizing process, it is expected that the recovery of zinc from the wastes or purification of heavy-metal-containing hazardous residues is technically feasible.展开更多
Heck reaction is one of the most important carbon-carbon bond forming reactions with wide applications in organic synthesis.Considerable advances of enantioselective Heck reaction have been achieved in the past decade...Heck reaction is one of the most important carbon-carbon bond forming reactions with wide applications in organic synthesis.Considerable advances of enantioselective Heck reaction have been achieved in the past decades.This review focuses on recent development of catalytic asymmetric Heck reaction and reductive Heck reaction,which covers intermolecular and intramolecular versions since 2011.The article is organized in terms of the cat-alysts and olefin substrates.展开更多
Chiral phosphine-containing skeletons play a pivotal role in bioactive natural products, pharmaceuticals, chiral catalysts, and ligands. Despite considerable progress has been made in the synthesis of chiral phosphoru...Chiral phosphine-containing skeletons play a pivotal role in bioactive natural products, pharmaceuticals, chiral catalysts, and ligands. Despite considerable progress has been made in the synthesis of chiral phosphorus compounds, the development of facile and modular methods to access chiral allylic phosphorus compounds remains challenging due to the simultaneous control required for reactivity, enantioselectivity, and stereoselectivity. Herein, we present a general and modular platform to achieve the asymmetric reductive cross-coupling of α-bromophosphonates and vinyl bromides, enabling the synthesis of highly valuable chiral allylic phosphonate products with remarkable yields, enantioselectivities, and stereoselectivities.展开更多
基金Project(50925417) supported by the China National Funds for Distinguished Young ScientistsProject(50830301) supported by the National Natural Science Foundation of China+1 种基金Projects(2010AA065203,2011AA061001) supported by the National High-tech Research Program of ChinaProject(NCET-10-0840) supported by the Program for New Century Excellent Talents in University,China
文摘A novel process for sulfidation of ZnO by co-grinding with sulfur and reductive additives （P, Fe, A1, and Mg） was developed. The sulfidation extent of ZnO with the addition of P, Fe, A1 or Mg can reach 85.2%, 81.6%, 96.7% and 92.6% after grinding for 4, 6, 1 and 1 h, respectively. Based on the chemical phase composition analysis and morphological characteristics of sulfidized products by XRD, SEM and TEM, a possible reaction mechanism, mechanically induced self-propagating reaction （MSR）, was proposed to explain the sulfidization reaction. In addition, the floatability of sulfidized products was investigated for the recovery of metal sulfide and ZnS can be concentrated with a high concentration ratio and concentrate grade. By using the sulfidizing process, it is expected that the recovery of zinc from the wastes or purification of heavy-metal-containing hazardous residues is technically feasible.
基金the National Natural Science Foundation of China(Nos.21702184,21772175,and 91956117)is gratefully acknowledged.
文摘Heck reaction is one of the most important carbon-carbon bond forming reactions with wide applications in organic synthesis.Considerable advances of enantioselective Heck reaction have been achieved in the past decades.This review focuses on recent development of catalytic asymmetric Heck reaction and reductive Heck reaction,which covers intermolecular and intramolecular versions since 2011.The article is organized in terms of the cat-alysts and olefin substrates.
基金supported by the National Natural Science Foundation of China (22071183)the Science and Technology Commission of Shanghai Municipality (19DZ2271500)。
文摘Chiral phosphine-containing skeletons play a pivotal role in bioactive natural products, pharmaceuticals, chiral catalysts, and ligands. Despite considerable progress has been made in the synthesis of chiral phosphorus compounds, the development of facile and modular methods to access chiral allylic phosphorus compounds remains challenging due to the simultaneous control required for reactivity, enantioselectivity, and stereoselectivity. Herein, we present a general and modular platform to achieve the asymmetric reductive cross-coupling of α-bromophosphonates and vinyl bromides, enabling the synthesis of highly valuable chiral allylic phosphonate products with remarkable yields, enantioselectivities, and stereoselectivities.
