72847-31-5Relevant articles and documents
Synthesis method of antioxidant 6PPD to reduce side reactions
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Paragraph 0016; 0018-0019, (2022/03/02)
The present invention belongs to the field of fine chemical technology, relates to a method of continuous synthesis of adhesive antioxidant 6PPD. The patent of the present invention uses a precious metal catalyst to synthesize antioxidant 6PPD on a fixed bed, the precious metal catalyst is loaded into a fixed bed reaction device, nitrogen is filled with 0.1 ~ 0.5MPa pressure and replaces the entire high pressure reactor system, after the reaction system is replaced, the temperature rises, and the flow rate of hydrogen is 0.1 ~ 1L / min. Using 4-aminodiphenylamine and similar organic matter and methyl isobutyl methyl ketone and acetone as raw materials, the synthesis test of the antioxidant 6PPD using a precious metal catalyst was carried out. Compared with the existing precious metal kettle hydrogenation process, it has continuous operation, simple operation, avoids the catalyst loss caused by the use of powder catalyst due to filtration, and can reduce production costs; compared with the existing copper catalyst, due to the improvement of catalyst selectivity, NO MIBC dehydrogenation device can be added, saving energy consumption and having superiority.
Chemoselective and Site-Selective Reductions Catalyzed by a Supramolecular Host and a Pyridine-Borane Cofactor
Morimoto, Mariko,Cao, Wendy,Bergman, Robert G.,Raymond, Kenneth N.,Toste, F. Dean
supporting information, p. 2108 - 2114 (2021/02/06)
Supramolecular catalysts emulate the mechanism of enzymes to achieve large rate accelerations and precise selectivity under mild and aqueous conditions. While significant strides have been made in the supramolecular host-promoted synthesis of small molecules, applications of this reactivity to chemoselective and site-selective modification of complex biomolecules remain virtually unexplored. We report here a supramolecular system where coencapsulation of pyridine-borane with a variety of molecules including enones, ketones, aldehydes, oximes, hydrazones, and imines effects efficient reductions under basic aqueous conditions. Upon subjecting unprotected lysine to the host-mediated reductive amination conditions, we observed excellent ?-selectivity, indicating that differential guest binding within the same molecule is possible without sacrificing reactivity. Inspired by the post-translational modification of complex biomolecules by enzymatic systems, we then applied this supramolecular reaction to the site-selective labeling of a single lysine residue in an 11-amino acid peptide chain and human insulin.
Reduction of α,β-unsaturated carbonyl compounds and 1,3-diketones in aqueous media, using a raney ni-al alloy
Simion, Cristian,Mitoma, Yoshiharu,Katayama, Yumi,Simion, Alina Marieta
, p. 51 - 55 (2021/02/03)
The treatment of α,β-unsaturated carbonyl compounds and 1,3-diketones with Raney Ni-Al alloy in aqueous media yielded as major reaction products the corresponding saturated alcohols and/or the corresponding hydrocarbons, in a complete transformation of the starting material.
Method for preparing alcohol compound through hydrogenation of carbonyl-containing compound
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Paragraph 0056-0058, (2021/07/10)
The invention provides a method for preparing an alcohol compound through hydrogenation of a carbonyl-containing compound, the method comprises the following steps: firstly, contacting the carbonyl-containing compound with a nickel catalyst precursor to obtain a nickel-containing solution, then carrying out a contact reaction on the nickel-containing solution and hydrogen, converting the contained nickel into a nickel catalyst, and carrying out in-situ catalysis on the hydrogenation reaction of the carbonyl-containing compound, and obtaining the alcohol compound. According to the preparation method provided by the invention, the preparation of the nickel catalyst and the hydrogenation reaction of the carbonyl-containing compound are carried out in the same technological process for the first time, the prepared nickel catalyst is good in catalytic activity and long in service life, and the alcohol compound prepared by in-situ catalysis is high in yield and good in selectivity, so that the production cost of the alcohol compound can be remarkably reduced, the production efficiency is improved, and the method is particularly suitable for large-scale industrial production.
Pickering-Droplet-Derived MOF Microreactors for Continuous-Flow Biocatalysis with Size Selectivity
Liang, Linfeng,Shi, Hu,Tian, Danping,Wang, Jun-Hao,Xue, Nan,Yang, Hengquan,Zhang, Xiaoming
supporting information, p. 16641 - 16652 (2021/10/20)
Enzymatic microarchitectures with spatially controlled reactivity, engineered molecular sieving ability, favorable interior environment, and industrial productivity show great potential in synthetic protocellular systems and practical biotechnology, but their construction remains a significant challenge. Here, we proposed a Pickering emulsion interface-directed synthesis method to fabricate such a microreactor, in which a robust and defect-free MOF layer was grown around silica emulsifier stabilized droplet surfaces. The compartmentalized interior droplets can provide a biomimetic microenvironment to host free enzymes, while the outer MOF layer secludes active species from the surroundings and endows the microreactor with size-selective permeability. Impressively, the thus-designed enzymatic microreactor exhibited excellent size selectivity and long-term stability, as demonstrated by a 1000 h continuous-flow reaction, while affording completely equal enantioselectivities to the free enzyme counterpart. Moreover, the catalytic efficiency of such enzymatic microreactors was conveniently regulated through engineering of the type or thickness of the outer MOF layer or interior environments for the enzymes, highlighting their superior customized specialties. This study provides new opportunities in designing MOF-based artificial cellular microreactors for practical applications.
Facile Stereoselective Reduction of Prochiral Ketones by using an F420-dependent Alcohol Dehydrogenase
Martin, Caterina,Tjallinks, Gwen,Trajkovic, Milos,Fraaije, Marco W.
, p. 156 - 159 (2020/10/26)
Effective procedures for the synthesis of optically pure alcohols are highly valuable. A commonly employed method involves the biocatalytic reduction of prochiral ketones. This is typically achieved by using nicotinamide cofactor-dependent reductases. In this work, we demonstrate that a rather unexplored class of enzymes can also be used for this. We used an F420-dependent alcohol dehydrogenase (ADF) from Methanoculleus thermophilicus that was found to reduce various ketones to enantiopure alcohols. The respective (S) alcohols were obtained in excellent enantiopurity (>99 % ee). Furthermore, we discovered that the deazaflavoenzyme can be used as a self-sufficient system by merely using a sacrificial cosubstrate (isopropanol) and a catalytic amount of cofactor F420 or the unnatural cofactor FOP to achieve full conversion. This study reveals that deazaflavoenzymes complement the biocatalytic toolbox for enantioselective ketone reductions.
Primary Alcohols via Nickel Pentacarboxycyclopentadienyl Diamide Catalyzed Hydrosilylation of Terminal Epoxides
Lambert, Tristan H.,Steiniger, Keri A.
, p. 8013 - 8017 (2021/10/25)
The efficient and regioselective hydrosilylation of epoxides co-catalyzed by a pentacarboxycyclopentadienyl (PCCP) diamide nickel complex and Lewis acid is reported. This method allows for the reductive opening of terminal, monosubstituted epoxides to form unbranched, primary alcohols. A range of substrates including both terminal and nonterminal epoxides are shown to work, and a mechanistic rationale is provided. This work represents the first use of a PCCP derivative as a ligand for transition-metal catalysis.
Reduction of α,β-Unsaturated carbonyl compounds and 1,3-Diketones in aqueous media, using a raney ni-al alloy
Katayama, Yumi,Mitoma, Yoshiharu,Simion, Alina Marieta,Simion, Cristian
, p. 51 - 55 (2020/07/23)
The treatment of α,β-unsaturated carbonyl compounds and 1,3-diketones with Raney Ni-Al alloy in aqueous media yielded as major reaction products the corresponding saturated alcohols and/or the corresponding hydrocarbons, in a complete transformation of the starting material.
Efficient Transfer Hydrogenation of Ketones Catalyzed by a Phosphine-Free Cobalt-NHC Complex
Ibrahim, Jessica Juweriah,Reddy, C. Bal,Fang, Xiaolong,Yang, Yong
, p. 4429 - 4432 (2020/07/04)
A simple phosphine-free cobalt-NHC pincer complex has been synthesized and utilized for the transfer hydrogenation of ketones with 2-propanol as hydrogen donor. A broad range of ketones varying from aromatic, aliphatic and heterocyclic were effectively reduced to their corresponding alcohols in moderate to excellent yields with good tolerance of functional groups.
Synthesis and characterization of new ruthenium(III) complexes derived from fluoreneamine-based Schiff base ligands and their catalytic activity in transfer hydrogenation of ketones
Balasubramani, Kasturi,Nagalakshmi, Veerasamy,Nandhini, Raja,Venkatachalam, Galmari
, (2020/03/16)
An easy and convenient synthesis of a new series of octahedral ruthenium(III) complexes bearing Schiff base ligands of general formula [RuCl2(EPh3)2(L)] (where E = P, As and L = O,N-donor Schiff bases) has been reported. The composition of all complexes has been unequivocally characterized by spectral (IR, UV-vis, EPR) and ESI-MS techniques. The substituted Schiff base ligands behave as bidentate O,N-donors and coordinate to ruthenium via the phenolic oxygen, the azomethine nitrogen. Complexes 1–6 have been proven to catalyze the transfer hydrogenation of linear, cyclic and aromatic ketones to their corresponding secondary alcohols in the presence of i-PrOH/KOH at 80 °C with conversion up to 99%. The effect of other variables on the transfer hydrogenation reaction such as solvent, base, and catalyst loading is also reported.
