C2 prenylated indoles are widespread in a variety of bioactive natural alkaloids.Therefore,theselective installation of prenyl group at C2 position of NH indoles is of great significance.However,the known protocols ge...C2 prenylated indoles are widespread in a variety of bioactive natural alkaloids.Therefore,theselective installation of prenyl group at C2 position of NH indoles is of great significance.However,the known protocols generally require a multi‐step procedure and stoichiometric promoters.Hereinwe develop a one‐step C2 prenylation of NH indole with cheap tert‐prenyl alcohol enabled by acidcatalysis.Salient features include good regioselectivity,step‐and atom‐economy,broad substratescope,and simple catalytic system.The mechanistic investigations demonstrate that both C2prenylation and C3 prenylation/migration pathways are engaged in the reaction.Notably,this practicalstrategy can be applied to the late‐stage diversification of tryptophan‐based peptides and concisesynthesis of tryprostatin B.展开更多
Single-atom catalysts(SACs)have emerged as one of the most competitive catalysts toward a variety of important electrochemical reactions,thanks to their maximum atom economy,unique electronic and geometric structures....Single-atom catalysts(SACs)have emerged as one of the most competitive catalysts toward a variety of important electrochemical reactions,thanks to their maximum atom economy,unique electronic and geometric structures.However,the role of SACs supports on the catalytic performance does not receive enough research attentions.Here,we report an efficient route for synthesis of single atom Zn loading on the N-doped carbon nano-onions(ZnN/CNO).ZnN/CNO catalysts show an excellent high selectivity for CO_(2) electro-reduction to CO with a Faradaic efficiency of CO(FECO)up to 97%at -0.47 V(vs.reversible hydrogen electrode,RHE)and remarkable durability without activity decay.To our knowledge,ZnN/CNO is the best activity for the Zn based catalysts up to now,and superior to single atom Zn loading on the two-dimensional planar and porous structure of graphene substrate,although the graphene with larger surface area.The exact role of such carbon nano-onions(CNO)support is studied systematically by coupling characterizations and electrochemistry with density functional theory(DFT)calculations,which have attributed such good performance to the increased curvature.Such increased curvature modifies the surface charge,which then changes the adsorption energies of key intermediates,and improves the selectivity for CO generation accordingly.展开更多
文摘C2 prenylated indoles are widespread in a variety of bioactive natural alkaloids.Therefore,theselective installation of prenyl group at C2 position of NH indoles is of great significance.However,the known protocols generally require a multi‐step procedure and stoichiometric promoters.Hereinwe develop a one‐step C2 prenylation of NH indole with cheap tert‐prenyl alcohol enabled by acidcatalysis.Salient features include good regioselectivity,step‐and atom‐economy,broad substratescope,and simple catalytic system.The mechanistic investigations demonstrate that both C2prenylation and C3 prenylation/migration pathways are engaged in the reaction.Notably,this practicalstrategy can be applied to the late‐stage diversification of tryptophan‐based peptides and concisesynthesis of tryprostatin B.
基金This work was supported by the National Key R&D Program of China(2020YFA0710404)the Beijing Natural Science Foundation(2182077)the National Natural Science Foundation of China(21477136,51972281,and 21703250).
文摘Single-atom catalysts(SACs)have emerged as one of the most competitive catalysts toward a variety of important electrochemical reactions,thanks to their maximum atom economy,unique electronic and geometric structures.However,the role of SACs supports on the catalytic performance does not receive enough research attentions.Here,we report an efficient route for synthesis of single atom Zn loading on the N-doped carbon nano-onions(ZnN/CNO).ZnN/CNO catalysts show an excellent high selectivity for CO_(2) electro-reduction to CO with a Faradaic efficiency of CO(FECO)up to 97%at -0.47 V(vs.reversible hydrogen electrode,RHE)and remarkable durability without activity decay.To our knowledge,ZnN/CNO is the best activity for the Zn based catalysts up to now,and superior to single atom Zn loading on the two-dimensional planar and porous structure of graphene substrate,although the graphene with larger surface area.The exact role of such carbon nano-onions(CNO)support is studied systematically by coupling characterizations and electrochemistry with density functional theory(DFT)calculations,which have attributed such good performance to the increased curvature.Such increased curvature modifies the surface charge,which then changes the adsorption energies of key intermediates,and improves the selectivity for CO generation accordingly.
