Day: April 20, 2022

HPLC of Formula: 13925-00-3. So far, in addition to halogen atoms, other non-metallic atoms can become part of the aromatic heterocycle, and the target ring system is still aromatic. Compound: 2-Ethylpyrazine, is researched, Molecular C6H8N2, CAS is 13925-00-3, about Acid activated montmorillonite for gas-phase catalytic dehydration of monoethanolamine.

The acid activated montmorillonite (Acid-Mt) was investigated for the first time as a catalyst for the gaseous-phase dehydration of monoethanolamine (MEA). A series of Acid-Mt was obtained by treating the Na-type montmorillonite (Na-Mt) at 104 °C in 3.2 mol L-1 HNO3 aqueous solution for 4-24 h followed by calcining at 450-1150 °C for 4 h, resp. The Acid-Mts were characterized by X-ray diffraction, temperature programmed desorption of NH3, temperature programmed desorption of CO2, and N2 adsorption-desorption, and were evaluated as catalysts for the gaseous-phase dehydration of MEA. With increasing the activation time or calcination temperature, both the amounts of acidic and basic sites over Acid-Mt were decreased, and more pronounced extent was observed in the case of changing the calcination temperature By correlating the catalytic results with the characterization results, the acidity of the catalyst was revealed to be the key factor in determining the MEA conversion. In contrast, a complex picture was observed in the case of the product selectivity. Generally, a higher acidity over Acid-Mt favored the intermol. dehydration and 1,2-elimination reactions of MEA, leading to a higher selectivity of piperazine (PIP) and triethylenediamine (TEDA). When the acidity of Acid-Mt was lower, the intramol. dehydration and deamination reactions were improved resulting in an increasing selectivity of ethyleneimine (EI). Importantly, the product distribution of the MEA dehydration was greatly regulated by the simply changing the acid activation parameters of Mt. Thus, Acid-Mt is a promising catalyst for selectively synthesizing different N-containing fine chems. via the MEA dehydration reaction.

Different reactions of this compound(2-Ethylpyrazine)HPLC of Formula: 13925-00-3 require different conditions, so the reaction conditions are very important.

Reference:
Chiral Catalysts,
Chiral catalysts – SlideShare

Heterocyclic compounds can be divided into two categories: alicyclic heterocycles and aromatic heterocycles. Compounds whose heterocycles in the molecular skeleton cannot reflect aromaticity are called alicyclic heterocyclic compounds. Compound: 13925-00-3, is researched, Molecular C6H8N2, about Characterization of the Key Aroma Compounds in Two Differently Dried Toona sinensis (A. Juss.) Roem. by Means of the Molecular Sensory Science Concept, the main research direction is aroma compound dried Toona leaf; aroma extract dilution analysis; aroma recombination; molecular sensory science concept; odor activity value; stable isotope dilution analysis.Application of 13925-00-3.

A systematic approach for the characterization of the key aroma-active compounds in sun-dried Toona sinensis (SDTS) and vacuum-dried T. sinensis (VDTS) was performed by means of the mol. sensory science concept. A total of 64 aroma-active compounds were identified via gas chromatog.-olfactometry (GC-O) and gas chromatog.-mass spectrometry (GC-MS). Aroma extract dilution anal. (AEDA) and static headspace dilution anal. revealed 39 odorants in SDTS and 32 odorants in VDTS with flavor dilution (FD) factors from 8 to 4096, with the highest for vanillin and eugenol in both samples. Stable isotope dilution anal. (SIDA) and an internal standard method were applied to quantitate 42 odorants, revealing 35 compounds in concentrations above their resp. odor thresholds in SDTS and 29 compounds in VDTS, resp. Calculation of odor activity values (OAVs) indicated 2-isopropyl-3-methoxypyrazine, eugenol, and β-ionone with the highest OAVs in both samples. Recombination experiments of the overall aromas of SDTS and VDTS by mixing the odorants with OAVs ≥1 in their naturally occurring concentrations proved the successful identification and quantitation of the resp. key odorants.

Different reactions of this compound(2-Ethylpyrazine)Application of 13925-00-3 require different conditions, so the reaction conditions are very important.

Reference:
Chiral Catalysts,
Chiral catalysts – SlideShare

HPLC of Formula: 542-58-5. The reaction of aromatic heterocyclic molecules with protons is called protonation. Aromatic heterocycles are more basic than benzene due to the participation of heteroatoms. Compound: 2-Chloroethyl acetate, is researched, Molecular C4H7ClO2, CAS is 542-58-5, about Perspective on diabatic models of chemical reactivity as illustrated by the gas-phase SN2 reaction of acetate ion with 1,2-dichloroethane. [Erratum to document cited in CA150:077105]. Author is Valero, Rosendo; Song, Lingchun; Gao, Jiali; Truhlar, Donald G..

The authors explain the confusion involved in using supplied parameters for the EVB to DhlA. The authors wish to retract all quant. results from their paper. The removal of the mol. mech. EVB calculations has no effect on the quantum mech. diabatic surfaces obtained by the 4-fold way and MOVB.

Different reactions of this compound(2-Chloroethyl acetate)HPLC of Formula: 542-58-5 require different conditions, so the reaction conditions are very important.

Reference:
Chiral Catalysts,
Chiral catalysts – SlideShare

In organic chemistry, atoms other than carbon and hydrogen are generally referred to as heteroatoms. The most common heteroatoms are nitrogen, oxygen and sulfur. Now I present to you an article called X-ray contrast agents. II. Synthesis of iodine compounds of α-picoline, published in 1954, which mentions a compound: 22468-26-4, mainly applied to , Quality Control of 4-Hydroxypicolinic acid.

Two new x-ray contrast agents, 3,5-diiodo-4-hydroxy-α-picoline (I) and 2-methyl-3,5-diiodo-4-pyridone-1-acetic acid (II) were prepared from α-picoline. 4-Chloro-α-picoline (2.6 g.), 3 g. AcONa, and 15 ml. AcOH heated 8 hrs. at 200°, the solvent evaporated in vacuo, the residue heated 1 hr. with 10% HCl, the mixture evaporated to dryness, taken up in EtOH, mixed with 5 ml. saturated aqueous NaHCO3, again evaporated, and dissolved in benzene gave 1.7 g. 4-hydroxy-α-picoline (III), m.p. indefinite; picrate, m. 199-200° (from MeOH). III (0.5 g.) dissolved in 20 ml. hot H2O containing 3 ml. concentrated HCl, treated with 1.8 g. ClI in 10% HCl, heated 0.5 hr. on water bath, the mixture diluted with 100 ml. hot H2O, acid added, the mixture cooled, the precipitate dissolved in NaOH solution and precipitated with dilute HCl gave 1.6 g. I, decomposing 239-41°. I (1 g.) in 10 ml. 10% NaOH refluxed 3 hrs. with 0.3 g. CH2ClCO2H in 4 ml. 10% Na2CO3, cooled, filtered, and the filtrate neutralized with 10% HCl gave 1 g. II, decomposing 230-2° (from dilute pyridine). III (1.5 g.) in 5 ml. 10% NaOH treated portionwise with 4.4 g. KMnO4 in 200 ml. of H2O at 80° with stirring, stirring and heating continued, the MnO2 filtered off, the filtrate neutralized with HCl and AcOH, evaporated, and cooled gave 4-pyridone-2-carboxylic acid (IV), decomposing 249-57° (from EtOH-benzene). 3,5-Diiodo-4-pyridone-2-carboxylic acid, decomposing 250-5°, was prepared from IV by the procedure of Dohrn and Diedrich (C.A. 26, 3506) and in a smaller yield by oxidizing I with KMnO4. 2,5-Diiodo-2-carboxy-4-pyridone-1-acetic acid, decomposing 223-4°, and 3,5-diiodo-1-methyl-4-pyridone-2-carboxylic acid, m. 159°, were prepared from the appropriate intermediates by the method of D. and D. (loc. cit.).

Different reactions of this compound(4-Hydroxypicolinic acid)Quality Control of 4-Hydroxypicolinic acid require different conditions, so the reaction conditions are very important.

Reference:
Chiral Catalysts,
Chiral catalysts – SlideShare

Most of the natural products isolated at present are heterocyclic compounds, so heterocyclic compounds occupy an important position in the research of organic chemistry. A compound: 22468-26-4, is researched, SMILESS is O=C(O)C1=NC=CC(O)=C1, Molecular C6H5NO3Journal, Comparative Study, Article, Research Support, U.S. Gov’t, P.H.S., Brain Research called Structure-function relationships for kynurenic acid analogs at excitatory pathways in the rat hippocampal slice, Author is Robinson, Michael B.; Schulte, Marvin K.; Freund, Ronald K.; Johnson, Rodney L.; Koerner, James F., the main research direction is kynurenate structure function hippocampus.COA of Formula: C6H5NO3.

Eight kynurenic acid analogs were bath-applied to rat hippocampal slices while recording extracellular synaptic field potentials, and the potencies of these analogs for inhibition of these responses were compared to that of kynurenic acid  [492-27-3]. Quinaldic acid  [93-10-7], 4-hydroxyquinoline  [611-36-9], 4-hydroxypicolinic acid  [22468-26-4], L-kynurenine  [2922-83-0], and picolinic acid  [98-98-6] inhibited evoked field potentials, but were at least 15-fold less potent than kynurenic acid in all pathways tested. Xanthurenic acid  [59-00-7] was inactive in the pathways tested. Quinolinic acid  [89-00-9] and dipicolinic acid  [499-83-2] showed signs of agonist activity with half-max ID’s of approx. 400 μM and 2500 μM, resp. Evidently, the 2-carboxy group and the 4-hydroxy moiety are essential for the antagonist activity exhibited by kynurenate. The unsubstituted 2nd aromatic ring greatly enhances the affinity of kynurenate for these receptors, and substitution in at least 1 position on this aromatic ring abolishes activity.

Different reactions of this compound(4-Hydroxypicolinic acid)COA of Formula: C6H5NO3 require different conditions, so the reaction conditions are very important.

Reference:
Chiral Catalysts,
Chiral catalysts – SlideShare