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Which is the most ehec-vs catalyst for amide hydrolysis? 

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As regards the formation of hydrogen, Au/CeO2 is the most effective catalyst.
It has been proposed that a dipeptide containing serine and histidine is an effective catalyst of amide hydrolysis, based on an apparent ability to degrade a protein.
The results show that TiO(2) is the best hydrolysis catalyst.
This is the most productive base-metal catalyst for dehydrogenative amidation reported to date, in some cases achieving up to 600 turnovers.
The type of metal ion catalysis observed in amide hydrolysis, i. e., pH independent or OH– dependent must be determined by the nature of the rate-determining step and the ease of C–N bond breaking.
Secondary amines appear to be more effective catalysts than the corresponding tertiary amines, and two amide derivatives exhibit only very slightly accelerated hydrolysis when compared with additive-free polycarbonate.
[1,8–11] Hence, the hydrolysis route following (1a) and/or (1b) is easier to activate with the assistance of a metal­based catalyst[12–20]
The results are somewhat unusual in that the most active catalyst is also the most selective.
The cationic triamine-amide yttrium catalysts are more active than the cationic amidinate catalysts of the same metal, possibly reflecting a stronger Y-amide bond in the latter, which is the more electron-deficient system.
Evidence for the acid catalysed hydrolysis of methyl ether linkage assisted by the neighboring amide function was obtained The hydrolysis rate of 1 to 3 was measured at least 1.7×103 fold higher than that of the reference compound 5 The values of thermodynamic parameters suggest that the participation of neighboring amide group in 1 is accompanied by a lower activation enthalpy with respect to the unassisted reaction in 5.

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What are synthesis methods of amides?4 answersAmides can be synthesized using various methods. One approach is the in-situ Grignard reagent formation in stirred suspensions of magnesium or calcium with hydryl halide and imine in THF, which allows the synthesis of amides with bulky silyl-free substituents. Another method is the electrochemical oxidative amidation, which involves the use of sodium iodide as both electrolyte and mediator in aqueous solution at room temperature, resulting in the synthesis of amides from benzyl alcohols and aldehydes with amines. Additionally, the acceptorless dehydrogenative coupling of epoxides and amines catalyzed by ruthenium pincer complexes can also be used to form amides, with H2 gas as the only byproduct. A one-pot synthesis of amides can be achieved by reacting isocyanate intermediates, generated in situ in the presence of 2-chloropyridine and trifluoromethanesulfonyl anhydride, with Grignard reagents. These methods provide efficient and diverse approaches for the synthesis of amides.
What are the different types of catalysts that can be used for catalytic hydrogenation of pitch?5 answersThere are several types of catalysts that can be used for catalytic hydrogenation of pitch. One type is the binary composite catalysts of Fe2O3-CoO/CaA and Fe2O3-CoO/ZSM-5, which contain iron and cobalt as CoFe2O4 compound and CoFe2O4 and CoFe respectively. Another type is the single-atom M-N3-B/C/N/O/S/P SACs, where M can be Co, Ni, Cu, Pt, Pd, or Ru, and they are anchored over dual-coordination N and other heteroatom-doped graphene catalysts. Additionally, there are photothermal catalysts that can be used for hydrogenation reactions, which harness concentrated sunlight to achieve the required reaction temperatures. Novel catalysts based on iron, copper, or zinc are also being explored as alternatives to the traditional transition metal catalysts. Finally, a Ti-Fe-Ni selective hydrogenation catalyst has been developed, which shows high activity and selectivity to olefins.
What is the most efficient process for hydrolysis?5 answersThe most efficient process for hydrolysis is the novel mercaptopropionic acid pressurized hydrolysis process. This process is energy-saving, shortens hydrolysis time, and prevents loss of mercaptopropionitrile. It involves feeding acidified hydrolysate into a hydrolysis kettle, heating and stirring, and maintaining a specific temperature and pressure for hydrolysis. Additionally, an efficient process for enzymatic hydrolysis of fats and oils is provided, which can convert more than 98% of fats into desired products. This process produces fatty acids, sn-regio mono-acylglycerol (MAG), sn-regio diacyl-glycerols (DAG), and glycerol. It also offers a process for producing fatty acids and glycerol with minimal sn-regio diacyl-glycerols (DAG) and sn-regio mono-acylglycerol (MAG). Another efficient process is the high efficient hydrolysis-acidification process for wastewater treatment, which improves treatment efficiency and removes soluble organic components more effectively. Furthermore, a combination of hydrolysis enzymes has been optimized for efficient hydrolysis of corn gluten meal, saving time while achieving similar results as single-enzyme hydrolysis.
What are the types of catalysts used for the HER?4 answersEfficient catalysts for the hydrogen evolution reaction (HER) include Pd-Ni-Fe alloys, a catalyst comprising a ruthenium single atom (Ru1) and nanoparticle (Run) loaded on a nitrogen-doped carbon substrate (Ru1-Run/CN), and transition metal catalysts bearing 2,2'-bipyridine-based ligand frameworks. Additionally, commercial Pt/C decorated with metal oxides (MOx-Pt/C) has been used as a catalyst for HER in alkaline conditions.
Amidation reaction for TiO2 based catalyst5 answersTiO2-based catalysts have been investigated for amidation reactions in several studies. Patil et al. prepared a TiO2/SnO2 nanocomposite catalyst and utilized it for the direct amidation reaction between amine derivatives and acetic acid, achieving excellent product yield at a moderate temperature. Özyağcı et al. used TiO2-supported catalysts immobilized on clinoptilolite for the esterification reaction of 1-octanol with acetic acid. Dutta et al. prepared a TiO2 encapsulated cuprous iodide catalyst and successfully applied it in the oxidative amidation of alkynes, synthesizing α-ketoarylamides from various substrates. Toyao et al. reported a TiO2-supported Re catalyst that promoted selective hydrogenation reactions, including the hydrogenation of esters to alcohols and the hydrogenation of amides to amines. Ali et al. found that Nb2O5 showed high activity in the direct amidation of esters with amines, giving high yields under solvent-free conditions.
What materials had been studied as catalysts for the HER?4 answersTransition metal dichalcogenide (TMD) materials, specifically tungsten disulfide (WS2) and molybdenum disulfide (MoS2), have been extensively studied as catalysts for the hydrogen evolution reaction (HER). Additionally, W-based dichalcogenides such as WS2, WSe2, and WTe2 have been investigated for their HER catalytic properties. Ni5P4 has also been identified as a promising catalyst for HER. Carbon-based materials, specifically heteroatom-doped graphene-like surfaced fibers, have been explored as metal-free catalysts for HER. Furthermore, Mo-based MXenes, including Mo2CO2, Mo2TiC2O2, and Mo2Ti2C3O2, have shown potential as catalysts for HER.

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