671-36-3Relevant articles and documents
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Weisman,G.R.,Nelson,S.F.
, p. 7007 (1976)
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Selective synthesis of formamides, 1,2-bis(N-heterocyclic)ethanes and methylamines from cyclic amines and CO2/H2 catalyzed by an ionic liquid-Pd/C system
Li, Ruipeng,Zhao, Yanfei,Wang, Huan,Xiang, Junfeng,Wu, Yunyan,Yu, Bo,Han, Buxing,Liu, Zhimin
, p. 9822 - 9828 (2019/11/11)
The reduction of CO2 with amines and H2 generally produces N-formylated or N-methylated compounds over different catalysts. Herein, we report the selective synthesis of formamides, 1,2-bis(N-heterocyclic)ethanes, and methylamines, which is achieved over an ionic liquid (IL, e.g., 1-butyl-3-methylimidazolium tetrafluoroborate, [BMIm][BF4])-Pd/C catalytic system. By simply varying the reaction temperature, formamides and methylamines can be selectively produced, respectively, in high yields. Interestingly, 1,2-bis(N-heterocyclic)ethanes can also be obtained via the McMurry reaction of the formed formamide coupled with subsequent hydrogenation. It was found that [BMIm][BF4] can react with formamide to form a [BMIm]+-formamide adduct; thus combined with Pd/C it can catalyze McMurry coupling of formamide in the presence of H2 to afford 1,2-bis(N-heterocyclic)ethane. Moreover, Pd/C-[BMIm][BF4] can further catalyze the hydrogenolysis of 1,2-bis(N-heterocyclic)ethane to access methylamine. [BMIm][BF4]-Pd/C was tolerant to a wide substrate scope, giving the corresponding formamides, 1,2-bis(N-heterocyclic)ethanes or methylamines in moderate to high yields. This work develops a new route to produce N-methylamine and opens the way to produce 1,2-bis(N-heterocyclic)ethane from cyclic amine as well.
Hydroamination/cyclization of aminoalkenes using cationic zirconocene and titanocene catalysts
Gribkov, Denis V.,Hultzsch, Kai C.
, p. 5542 - 5546 (2007/10/03)
Alternative catalysts: The hydroamination of nonactivated double bonds has been the domain of rare-earth-metal catalysts. Now alkyl zirconocene and titanocene cations, which are readily prepared from commercially available precursors, are shown to be active catalysts in the hydroamination/cyclization of secondary aminoalkenes to give tertiary pyrrolidines and piperidines.
Piperidylidene derivatives of carboxy-5H-dibenzo[a,d]cycloheptene
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, (2008/06/13)
The new 1-alkyl-4-(1, 2, or 3-carboxy-5H-dibenzo[a,d]cyclohepten-5-ylidene)-piperidine compounds are prepared from the corresponding 1, 2 or 3-carboxy-5H-dibenzo[a,d]cyclohepten-5-one by reaction with a Grignard reagent prepared from a 1-alkyl-4-halo piperidine to form an intermediate carbinol, or a 1, 2 or 3-carboxy-5-(1-alkyl-4-piperidyl)-5H-dibenzo[a,d]cyclohepten-5-ol which is then dehydrated to produce the desired 1-alkyl-4-(1, 2 or 3-carboxy-5H-dibenzo[a,d]cyclohepten-5-ylidene)-piperidine, or alternatively by hydrolysis of a 1-alkyl-4-(1, 2 or 3-cyano-5H-dibenzo[a,d]cyclohepten-5-ylidene)-piperidine compound to form the corresponding 1-alkyl-4-(1, 2 or 3-carboxy-5H-dibenzo[a,d]cyclohepten-5-ylidene)-piperidine compound.
