The Vaska’s complex—tris(pentafluorophenyl)borane combination was found to be a highly efficient cooperative catalysis system for the hydrosilylative reduction of tertiary amides to yield amines under mild condition...The Vaska’s complex—tris(pentafluorophenyl)borane combination was found to be a highly efficient cooperative catalysis system for the hydrosilylative reduction of tertiary amides to yield amines under mild conditions.The reaction shows high chemoselectivity,tolerating halide,phenolyl,alkenyl,nitro,nitrile,ester,azido,ketone,and enone functional groups.For unsubstituted cyclohexanone carboxamide,two variations were established to achieve either catalytic concomitant reduction of the two carbonyl groups or selective reduction of the amide carbonyl.The protocol was applied to the efficient synthesis and latestage modification of several pharmaceuticals and derivatives.Importantly,we showed that by simply prolonging reaction time to 24–28 h,the reaction can reach an exceptionally high efficiency with turnover number(TON)up to 9.8×10^(6) and turnover frequency(TOF)up to 408,333 at a quite low catalyst loading of 0.00001 mol%(S/C(Ir)=10,000,000).展开更多
The efficient construction of functionalized polycyclic structures is an imports nt objective in organic synthesis.Herein,we disclose a three-step"[2+n]"annulation method for the transformation of cyclic ket...The efficient construction of functionalized polycyclic structures is an imports nt objective in organic synthesis.Herein,we disclose a three-step"[2+n]"annulation method for the transformation of cyclic ketones to fused enimines and enones.The method relies on the Suzuki coupling reaction and the amide reductive alkenylation reaction.A series of fused bicyclic(6/6,6/7,8/7)and tricyclic(6/6/6;6/6/7,6/5/7)ring systems bearing an α,β-enimine or an α,β-enone functionality have been synthetized in good overall yields.展开更多
Carbocycles are ubiquitous in natural organic molecules and medicinal agents. Therefore, developing methodologies for the efficie nt con struction of car bo cycles constitutes an importa nt goal in organic synthesis. ...Carbocycles are ubiquitous in natural organic molecules and medicinal agents. Therefore, developing methodologies for the efficie nt con struction of car bo cycles constitutes an importa nt goal in organic synthesis. In this regard, for the construction of sixmembered rings, the Diels-Alder [4+2] cycloaddition reaction (Figure 1, eq 1) and Robinson annulation (Figure 2, eq 1) represent two paradigms in terms of efficiency, selectivity, and versatility.展开更多
基金supported by the National Natural Science Foundation of China(21931010)。
文摘The Vaska’s complex—tris(pentafluorophenyl)borane combination was found to be a highly efficient cooperative catalysis system for the hydrosilylative reduction of tertiary amides to yield amines under mild conditions.The reaction shows high chemoselectivity,tolerating halide,phenolyl,alkenyl,nitro,nitrile,ester,azido,ketone,and enone functional groups.For unsubstituted cyclohexanone carboxamide,two variations were established to achieve either catalytic concomitant reduction of the two carbonyl groups or selective reduction of the amide carbonyl.The protocol was applied to the efficient synthesis and latestage modification of several pharmaceuticals and derivatives.Importantly,we showed that by simply prolonging reaction time to 24–28 h,the reaction can reach an exceptionally high efficiency with turnover number(TON)up to 9.8×10^(6) and turnover frequency(TOF)up to 408,333 at a quite low catalyst loading of 0.00001 mol%(S/C(Ir)=10,000,000).
基金the National Natural Science Foundation of China(Nos.21672176 and 21332007)the National Key R&D Program of China(grant No.2017YFA0207302)the Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT)of Ministry of Education.
文摘The efficient construction of functionalized polycyclic structures is an imports nt objective in organic synthesis.Herein,we disclose a three-step"[2+n]"annulation method for the transformation of cyclic ketones to fused enimines and enones.The method relies on the Suzuki coupling reaction and the amide reductive alkenylation reaction.A series of fused bicyclic(6/6,6/7,8/7)and tricyclic(6/6/6;6/6/7,6/5/7)ring systems bearing an α,β-enimine or an α,β-enone functionality have been synthetized in good overall yields.
文摘Carbocycles are ubiquitous in natural organic molecules and medicinal agents. Therefore, developing methodologies for the efficie nt con struction of car bo cycles constitutes an importa nt goal in organic synthesis. In this regard, for the construction of sixmembered rings, the Diels-Alder [4+2] cycloaddition reaction (Figure 1, eq 1) and Robinson annulation (Figure 2, eq 1) represent two paradigms in terms of efficiency, selectivity, and versatility.
