39260-89-4Relevant academic research and scientific papers
Phosphine-Free Manganese Catalyst Enables Selective Transfer Hydrogenation of Nitriles to Primary and Secondary Amines Using Ammonia-Borane
Sarkar, Koushik,Das, Kuhali,Kundu, Abhishek,Adhikari, Debashis,Maji, Biplab
, p. 2786 - 2794 (2021/03/03)
Herein we report the synthesis of primary and secondary amines by nitrile hydrogenation, employing a borrowing hydrogenation strategy. A class of phosphine-free manganese(I) complexes bearing sulfur side arms catalyzed the reaction under mild reaction conditions, where ammonia-borane is used as the source of hydrogen. The synthetic protocol is chemodivergent, as the final product is either primary or secondary amine, which can be controlled by changing the catalyst structure and the polarity of the reaction medium. The significant advantage of this method is that the protocol operates without externally added base or other additives as well as obviates the use of high-pressure dihydrogen gas required for other nitrile hydrogenation reactions. Utilizing this method, a wide variety of primary and symmetric and asymmetric secondary amines were synthesized in high yields. A mechanistic study involving kinetic experiments and high-level DFT computations revealed that both outer-sphere dehydrogenation and inner-sphere hydrogenation were predominantly operative in the catalytic cycle.
Rapid Conventional and Microwave-Assisted Decarboxylation of L-Histidine and Other Amino Acids via Organocatalysis with R-Carvone under Superheated Conditions
Jackson, Douglas M.,Ashley, Robert L.,Brownfield, Callan B.,Morrison, Daniel R.,Morrison, Richard W.
, p. 2691 - 2700 (2015/12/18)
This article reports a new methodology taking advantage of superheated chemistry via either microwave or conventional heating for the facile decarboxylation of alpha amino acids using the recoverable organocatalyst, R-carvone. The decarboxylation of amino acids is an important synthetic route to biologically active amines, and traditional methods of amino acid decarboxylation are time consuming (taking up to several days in the case of L-histidine), are narrow in scope, and make use of toxic catalysts. Decarboxylations of amino acids including L-histidine occur in just minutes while replacing toxic catalysts with green catalyst, spearmint oil. Yields are comparable to or exceed previous methods and purification of product ammonium chloride salts is aided by an isomerization reaction of residual catalyst to phenolic carvacrol. The method has been shown to be effective for the decarboxylations of a range of natural, synthetic, and protected amino acids.
Straightforward access to cyclic amines by dinitriles reduction
Laval, Stéphane,Dayoub, Wissam,Pehlivan, Leyla,Métay, Estelle,Favre-Reguillon, Alain,Delbrayelle, Dominique,Mignani, Gérard,Lemaire, Marc
supporting information, p. 975 - 983 (2014/01/23)
1,1,3,3-Tetramethyldisiloxane (TMDS) and polymethylhydrosiloxane (PMHS), when associated with titanium(IV) isopropoxide, provide two convenient systems for the reduction of nitriles into the corresponding primary amines. Kinetics of the two systems have been studied by 1H NMR and demonstrated that reduction with PMHS occurs faster than with TMDS. These two titanium-based systems reduce both aromatic and aliphatic nitriles in the presence of Br, CC, NO2, OH, and cyclopropyl-ring. In the case of cyclopropyl-nitriles, the formation of secondary amines, which come from an intermolecular reductive alkylation reaction was observed. This result was exploited for the reduction of dinitriles, which led, in one-step, to azepane, piperidine, pyrrolidine, and azetidine derivatives through an intramolecular reductive alkylation reaction.
HISTAMINE H3 INVERSE AGONISTS AND ANTAGONISTS AND METHODS OF USE THEREOF
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Page/Page column 112, (2010/08/18)
Provided herein are fused imidazolyl compounds, methods of synthesis, and methods of use thereof. The compounds provided herein are useful for the treatment, prevention, and/or management of various disorders, such as neurological disorders and metabolic disorders. Compounds provided herein inhibit the activity of histamine H3 receptors and modulate the release of various neurotransmitters, such as histamine, acetylcholine, norepinephrine, and dopamine (e.g. at the synapse). Pharmaceutical formulations containing the compounds and their methods of use are also provided herein.
A mild and efficient method for the reduction of nitriles
Laval, Stéphane,Dayoub, Wissam,Favre-Reguillon, Alain,Berthod, Mika?l,Demonchaux, Patrice,Mignani, Gérard,Lemaire, Marc
experimental part, p. 7005 - 7007 (2010/02/28)
A simple and useful method for the reduction of nitriles into the corresponding amines using a tetramethyldisiloxane/titanium(IV) isopropoxide reducing system is described. The synthetic approach is straightforward and provides primary amines as hydrochloride salt in almost quantitative yield. Other advantages of this method, such as easy-to-handle hydride source, inert by-products, that is, TiO2 and oligomeric siloxanes, make it very attractive to prepare primary amines.
Potential modes of interaction of 9-aminomethyl-9,10-dihydroanthracene (AMDA) derivatives with the 5-HT2A receptor: A ligand structure-affinity relationship, receptor mutagenesis and receptor modeling investigation
Runyon, Scott P.,Mosier, Philip D.,Roth, Bryan L.,Glennon, Richard A.,Westkaemper, Richard B.
experimental part, p. 6808 - 6828 (2009/10/17)
The effects of 3-position substitution of 9-aminomethy 1-9,10- dihydroanthracene (AMDA) on 5-HT2A receptor affinity were determined and compared to a parallel series of DOB-like 1-(2,5-dimethoxyphenyl)-2- aminopropanes substituted at the 4-position. The results were interpreted within the context of 5-HT2A receptor models that suggest that members of the DOB-like series can bind to the receptor in two distinct modes that correlate with the compounds' functional activity. Automated ligand docking and molecular dynamics suggest that all of the AMDA derivatives, the parent of which is a 5-HT2A antagonist, bind in a fashion analogous to that for the sterically demanding antagonist DOB-like compounds. The failure of the F340 6.52L mutation to adversely affect the affinity of AMDA and the 3-bromo derivative is consistent with the proposed modes of orientation. Evaluation of ligand-receptor complex models suggest that a valine/threonine exchange between the 5-HT2A and D2 receptors may be the origin of selectivity for AMDA and two substituted derivatives.
