31844-65-2Relevant academic research and scientific papers
Cp*Ir complex bearing a flexible bridging and functional 2,2′-methylenebibenzimidazole ligand as an auto-tandem catalyst for the synthesis of N-methyl tertiary amines from imines via transfer hydrogenation/N-methylation with methanol
Ai, Yao,Chen, Xiaozhong,Li, Feng,Liu, Peng,Yang, Chenchen,Yang, Jiazhi
, p. 325 - 334 (2021/10/07)
A Cp*Ir complex bearing a flexible bridging and functional 2,2′-methylenebibenzimidazole ligand was designed, synthesized, and found to be a general and efficient auto-tandem catalyst for the synthesis of N-methyl tertiary amines from imines via transfer hydrogenation/N-methylation with methanol as both hydrogen source and methylating reagent. In the presence of [Cp*Ir(2,2′-CH2BiBzImH2)Cl][Cl], a range of desirable products were obtained in high yields with nearly complete selectivities. The reaction is highly attractive due to the highly atom economy, and minimal consumption of chemicals and energy. Notably, this research exhibits new potential of metal–ligand bifunctional catalysts for the activation of methanol as C1 source for organic synthesis.
Simplified preparation of a graphene-co-shelled Ni/NiO@C nano-catalyst and its application in theN-dimethylation synthesis of amines under mild conditions
Liu, Jianguo,Ma, Longlong,Song, Yanpei,Zhang, Mingyue,Zhuang, Xiuzheng
supporting information, p. 4604 - 4617 (2021/06/30)
The development of Earth-abundant, reusable and non-toxic heterogeneous catalysts to be applied in the pharmaceutical industry for bio-active relevant compound synthesis remains an important goal of general chemical research.N-methylated compounds, as one of the most essential bioactive compounds, have been widely used in the fine and bulk chemical industries for the production of high-value chemicals. Herein, an environmentally friendly and simplified method for the preparation of graphene encapsulated Ni/NiO nanoalloy catalysts (Ni/NiO@C) was developed for the first time, for the highly selective synthesis ofN-methylated compounds using various functional amines and aldehydes under easy to handle, and industrially applicable conditions. A large number of primary and secondary amines (more than 70 examples) could be converted to the correspondingN,N-dimethylamines with the participation of different functional aldehydes, with an average yield of over 95%. A gram-scale synthesis also demonstrated a similar yield when compared with the benchmark test. In addition, it was further proved that the catalyst could easily be recycled because of its intrinsic magnetism and reused up to 10 times without losing its activity and selectivity. Also, for the first time, the tandem synthesis ofN,N-dimethylamine products in a one-pot process, using only a single earth-abundant metal catalyst, whose activity and selectivity were more than 99% and 94%, respectively, for all tested substrates, was developed. Overall, the advantages of this newly developed method include operational simplicity, high stability, easy recyclability, cost-effectiveness of the catalyst, and good functional group compatibility for the synthesis ofN-methylation products as well as the industrially applicable tandem synthesis process.
Multimodal Anion Exchange Matrices
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Paragraph 0081; 0083; 0087, (2015/11/23)
The invention discloses a separation matrix which comprises a plurality of separation ligands, defined by the formula R1-L1-N(R3)-L2-R, immobilized on a support, wherein R1 is a five- or six-membered, substituted or non-substituted ring structure or a hydroxyethyl or hydroxypropyl group; L1 is either a methylene group or a covalent bond; R2 is a five- or six-membered, substituted or non-substituted ring structure; L2 is either a methylene group or a covalent bond; R3 is a methyl group; and wherein if R1 is a hydroxyethyl group and L1 is a covalent bond, R2 is a substituted aromatic ring structure or a substituted or non-substituted aliphatic ring structure.
Formation of benzylamines from triazene compounds via a 1,2-proton shift
Nishiwaki, Keiji,Ogawa, Takashi,Shigeta, Kazumi,Takahashi, Koichi,Matsuo, Keizo
, p. 7034 - 7042 (2007/10/03)
A new approach to benzylamines using triazene compounds has been developed that is facilitated by the lithiation of aryltriazenes followed by treatment with an electrophile. The regioselectivity of the reaction can be controlled by means of the substituents in the aryl group. The reaction contains the following steps: intramolecular carbon-carbon bond formation involving lithiation of an alkyl group on a 3-nitrogen atom; a 1,2-proton shift; and the subsequent release of nitrogen gas. Through the use of a deuterated triazene, we were able to determine that the reaction proceeds through a 1,2-proton shift.
Efficient synthesis of tertiary amines from secondary amines
Kurosu, Michio,Dey, Sevendu Sekhar,Crick, Dean C.
, p. 4871 - 4875 (2007/10/03)
Reliable N-alkylations of secondary amines have been developed. By using DIAD and TPP (or PS-TPP) a variety of secondary amines can be converted to the corresponding tertiary amines in good to excellent yields with diverse alkylhalides; no formation of quaternary amine salts are observed. These protocols are amenable to combinatorial chemistry libraries, and are also useful for the syntheses of secondary amines by an acid lysis of the cleavable tertiary amino resins.
α-lithiation of 1-Aryl-3,3-dialkyltriazenes and intramolecular conversion to benzylamine and tetrahydrobenzotriazine derivatives
Nishiwaki, Keiji,Ogawa, Takashi,Matsuo, Keizo
, p. 484 - 486 (2007/10/03)
An alternative route to benzylamine derivatives is provided by the lithiation of aryltriazenes followed by treatment with an electrophile [Eq. (1)]. The regioselectivity of the reaction can be controlled by means of the substituents X. When the 2- and 6-p
Catalytic amination of aldehydes to amides
Tillack, Annegret,Rudloff, Ivo,Beller, Matthias
, p. 523 - 528 (2007/10/03)
Aldehydes react in a disproportionation reaction in the presence of rhodium catalysts to yield amines and amides. By adding N-methylmorpholine N-oxide as an oxidant in the presence of catalytic amounts of rhodium, the oxidative amination of aldehydes proceeds selectively to give the corresponding amide. Both aliphatic and aromatic aldehydes react with secondary amines to yield carboxylic acid amides in good to excellent yields.
A general synthesis of amines and hydrazines by oxidation of amidocuprates and zinc-amidocuprates
Cane,Brancaleoni,Dembech,Ricci,Seconi
, p. 545 - 548 (2007/10/03)
A wide range of amines and hydrazines were synthesized according to an electrophilic amination protocol by oxidative decomposition of readily generated lithium- and zinc-amidocyanocuprates. Optimization of the yields was achieved by the appropriate combination of the organometallic cluster and the nature of the oxidizing agent.
Oxidative intramolecular coupling of amidocuprates as a novel route to amines and hydrazines
Alberti, Angelo,Cane, Francesco,Dembech, Pasquale,Lazzari, Dario,Ricci, Alfredo,Seconi, Giancarlo
, p. 1677 - 1681 (2007/10/03)
Amidocuprates, derived from organocopper reagents and lithium amides upon exposure to oxygen at low temperature, provide new amine derivatives in satisfactory yields. Details of this flexible and simple methodology are given. The reaction mechanism is analyzed in terms of an oxidative intramolecular coupling of aminyl radicals with the ligands on Cu in the intermediate amidocuprate. This reaction is a mild and efficient method for N-alkylation, -vinylation, and -arylation by which a number of amines, not easily accessible by normal routes, can be synthesized. Once applied to lithium hydrazides, it also provides a new and straightforward entry to N-substituted hydrazines.
