Month: January 2023

Conjugation of a double bond with an aromatic nucleus. XXV. The Schiff base in the Diels-Alder reaction was written by Tamayo, M. Lora;Alvarez, Francisco. And the article was included in Anales de la Real Sociedad Espanola de Fisica y Quimica, Serie A: Fisica in 1952.HPLC of Formula: 51488-33-6 This article mentions the following:

Substituted Schiff bases containing the conjugated diene system C:C.C:N, the C:C being a part of the aromatic nucleus, are treated with various dienophiles such as maleic anhydride (I) and Et maleate (II). The substituted groups studied are MeO, Me, -OCH₂O- and NO₂. In none of the attempted condensations does a 1,4-addition occur. The Schiff bases RCH:NPh, where R = m-MeOC₆H₄, 3,4-Me₂C₆H₃ (VI), 3,4-CH₂O₂C₆H₃ (III), m-O₂NC₆H₄ (IV), and 3,4-(MeO)₂C₆H₃, are refluxed 3 hrs. with I in a solvent (C₆H₆ or PhMe). The only reaction product identified is PhNHCOCH:-CHCO₂H, m. 193°. Schiff bases containing hydroquinone (V) heated 3 hrs. at 160° with II under anhydrous conditions do not react. Only III and IV in the absence of V give brownish-black resinous substances which are infusible below 360°, insoluble in organic solvents, soluble in concentrated H₂SO₄ and hot 20% NaOH. An addnl. Schiff base, 3-(p-MeOC₆H₄N:)CH-C₆H₄NO₂ (VII) refluxed 3 hrs. with I in a solvent (C₆H₆ or PhMe) gives only p-(MeO)C₆H₄NHCOCH:CHCO₂H. VII and II heated 3 hrs. at 160° and then allowed to stand a day do not react in the presence of V; in the absence of V is obtained a yellowish brown amorphous solid, believed to be a copolymer with the empirical formula (C₂₂H₂₄O₇₂)_x, m. indefinitely 143-9°, soluble in alc. and NaOH, and precipitated by acids and H₂O. VI and VII are new. For VI, 4.5 g. 3,4-Me₂C₆H₃CHO and 3.1 g. PhNH₂ are stirred 0.5 hr., let stand 24 hrs., and distilled to give 75% VI, colorless oil, b₁₅ 182°. For VII 3 g. p-anisidine and 2.7 g. m-O₂NC₆H₄CHO are refluxed 3 hrs. in 20 cc. absolute alc. and let stand 24 hrs.; the pale green crystalline plates, filtered and recrystallized from alc. and H₂O, m. 72° (yield 85%). In the experiment, the researchers used many compounds, for example, 3,4-Dimethoxybenzimidamide hydrochloride (cas: 51488-33-6HPLC of Formula: 51488-33-6).

3,4-Dimethoxybenzimidamide hydrochloride (cas: 51488-33-6) belongs to ethers. Relative to alcohols, ethers are generally less dense, are less soluble in water, and have lower boiling points. They are relatively unreactive, and as a result they are useful as solvents for fats, oils, waxes, perfumes, resins, dyes, gums, and hydrocarbons. Vapours of certain ethers are used as insecticides, miticides, and fumigants for soil. The unique properties of ethers (i.e., that they are strongly polar, with nonbonding electron pairs but no hydroxyl group) enhance the formation and use of many reagents. For example, Grignard reagents cannot form unless an ether is present to share its lone pair of electrons with the magnesium atom. Complexation of the magnesium atom stabilizes the Grignard reagent and helps to keep it in solution.HPLC of Formula: 51488-33-6

Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem

Effects of glymes on the distribution of Mg(B10H10) and Mg(B12H12) from the thermolysis of Mg(BH4)2 was written by Tran, Ba L.;Allen, Tamara N.;Bowden, Mark E.;Autrey, Tom;Jensen, Craig M.. And the article was included in Inorganics in 2021.Related Products of 112-49-2 This article mentions the following:

We examined the effects of concentrations and identities of various glymes, from monoglyme up to tetraglyme, on H₂ release from the thermolysis of Mg(BH4)2 at 160-200°C for 8 h. ¹¹B NMR anal. shows major products of Mg(B₁₀H₁₀) and Mg(B₁₂H₁₂); however, their relative ratio is highly dependent both on the identity and concentration of the glyme to Mg(BH₄)₂. Selective formation of Mg(B₁₀H₁₀) was observed with an equivalent of monoglyme and 0.25 equiv of tetraglyme. However, thermolysis of Mg(BH₄)₂ in the presence of stoichiometric or greater equivalent of glymes can lead to unselective formation of Mg(B₁₀H₁₀) and Mg(B₁₂H₁₂) products or inhibition of H₂ release. In the experiment, the researchers used many compounds, for example, 2,5,8,11-Tetraoxadodecane (cas: 112-49-2Related Products of 112-49-2).

2,5,8,11-Tetraoxadodecane (cas: 112-49-2) belongs to ethers. Of all the functional groups, ethers are the least reactive ones. Ether bonds are quite stable towards bases, oxidizing agents and reducing agents. The unique properties of ethers (i.e., that they are strongly polar, with nonbonding electron pairs but no hydroxyl group) enhance the formation and use of many reagents. For example, Grignard reagents cannot form unless an ether is present to share its lone pair of electrons with the magnesium atom. Complexation of the magnesium atom stabilizes the Grignard reagent and helps to keep it in solution.Related Products of 112-49-2

Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem

Photocatalyzed decarboxylation of oxamic acids under near-infrared conditions was written by Ogbu, Ikechukwu Martin;Bassani, Dario M.;Robert, Frederic;Landais, Yannick. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2022.Computed Properties of C5H12O3 This article mentions the following:

Photocatalyzed oxidative decarboxylation of oxamic acids under near-IR irradiation using Os(bptpy)₂(PF₆)₂ as catalyst was reported. The reaction was applied to the synthesis of urethanes RNHC(O)OR¹ [R = (CH₂)₂C₆H₅, 4-ClC₆H₄CH₂, cyclohexyl, etc.; R¹ = Et, i-Pr, CH₂CF₃, etc.] and heterocyclic amides. Mechanistic studies and comparative penetration depths between the NIR and the visible light mediated processes were discussed. In the experiment, the researchers used many compounds, for example, 2-(2-Methoxyethoxy)ethanol (cas: 111-77-3Computed Properties of C5H12O3).

2-(2-Methoxyethoxy)ethanol (cas: 111-77-3) belongs to ethers. Of all the functional groups, ethers are the least reactive ones. Ether bonds are quite stable towards bases, oxidizing agents and reducing agents. But on the other hand, ethers undergo cleavage by reaction with acids. Autoxidation is the spontaneous oxidation of a compound in air. In the presence of oxygen, ethers slowly autoxidize to form hydroperoxides and dialkyl peroxides. If concentrated or heated, these peroxides may explode. To prevent such explosions, ethers should be obtained in small quantities, kept in tightly sealed containers, and used promptly.Computed Properties of C5H12O3

Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem

Alkaline hydrolysis of nuclear-substituted ethyl cinnamates. Cumulative effects of substituents was written by Jones, Brynmor;Watkinson, J. G.. And the article was included in Journal of the Chemical Society in 1958.HPLC of Formula: 6972-61-8 This article mentions the following:

The introduction of substituents, even at the ο-position, causes no change in the nonexponential entropy term in the Arrhenius equation. The cumulative effect of 2 substituents in the 2- and 4-, and also in the 3- and 5-positions are additive, giving log₁₀A 9.8-10.0, but in other positions there are sometimes large significant variations in the energies of activation compared with that calculated by ΔE’ = 2.303 RT log₁₀k/k₀, e.g. the factor 100 k_calculated/k_obs. = 50 for Et 2,3-dimethoxycinnamate, and 58 for Et 2,3,4-trimethoxycinnamate, which indicates steric interference with mesomeric electron release from the 2-position, as confirmed by the analogous case of the 4-position in Et 3,4,5-trimethoxybenzoate where the factor = 25. Slight significant deviations for 3,4-dialkoxycinnamates may be due to steric and/or polar interactions. Hydrolyses were carried out at 24.8° and other temperatures in 85.4% aqueous EtOH, the initial concentrations of CO₂-free NaOH and ester were equal at 0.05M, and the reactions strictly 2nd order. New compounds prepared via the substituted BzH and esterification are Et m-methylcinnamate, b₁₀ 146°, Et 2,4-dichlorocinnamate, b₅ 162° and m. 53.5°, Et 3,5-dichlorocinnamate, b₁₂ 178°, and m. 74°, Et 3,6-dichlorocinnamate, b₂ 156° and m. 56°, Et 3-chloro-4-methoxycinnamate, b₄ 170° and m. 61° (3-chloro-4-methoxycinnamic acid m. 244°), Et 3-methyl-4-methoxycinnamate, b₁₁ 184° and m. 36.5° (3-methyl-4-methoxycinnamic acid m. 201°), Et 2,3,4-trimethoxycinnamate, b₁₄ 207° and m. 50°, and Et 4-ethoxy-3-methoxycinnamate, m. 109.5° [4-ethoxy-3-methoxycinnamic acid m. 200° (decomposition)]. In the experiment, the researchers used many compounds, for example, 3-(2,4-Dimethoxyphenyl)acrylic acid (cas: 6972-61-8HPLC of Formula: 6972-61-8).

3-(2,4-Dimethoxyphenyl)acrylic acid (cas: 6972-61-8) belongs to ethers. Ether is less polar than esters, alcohols or amines because of the oxygen atom that is unable to participate in hydrogen bonding due to the presence of bulky alkyl groups on both sides of the oxygen atom. At room temperature, ethers are pleasant-smelling colourless liquids. Relative to alcohols, ethers are generally less dense, are less soluble in water, and have lower boiling points. They are relatively unreactive, and as a result they are useful as solvents for fats, oils, waxes, perfumes, resins, dyes, gums, and hydrocarbons. Vapours of certain ethers are used as insecticides, miticides, and fumigants for soil.HPLC of Formula: 6972-61-8

Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem

Palladium-Catalyzed Synthesis of 2,3-Disubstituted 5-Azaindoles via Heteroannulation Reaction and of 2-Substituted 5-Azaindoles through Domino Sila-Sonogashira/5-Endo Cyclization was written by Livecchi, Marion;Calvet, Geraldine;Schmidt, Frederic. And the article was included in Journal of Organic Chemistry in 2012.Formula: C6H10O2 This article mentions the following:

A general and efficient procedure for the synthesis of 2,3-disubstituted 5-azaindoles, e.g. I, through the palladium-catalyzed heteroannulation of 4-acetamido-3-iodopyridines and diaryl-, dialkyl-, or arylalkylalkynes is described along with a study of the reaction regioselectivity. The preparation of 2-monosubstituted 5-azaindoles via sila-Sonogashira/5-endo cyclization is also reported. These methods allowed us to prepare 36 diversely substituted 5-azaindoles in good yields. In the experiment, the researchers used many compounds, for example, 1,4-Dimethoxy-2-butyne (cas: 16356-02-8Formula: C6H10O2).

1,4-Dimethoxy-2-butyne (cas: 16356-02-8) belongs to ethers. Relative to alcohols, ethers are generally less dense, are less soluble in water, and have lower boiling points. They are relatively unreactive, and as a result they are useful as solvents for fats, oils, waxes, perfumes, resins, dyes, gums, and hydrocarbons. Vapours of certain ethers are used as insecticides, miticides, and fumigants for soil. Electron-deficient reagents are also stabilized by ethers. For example, borane (BH3) is a useful reagent for making alcohols. Pure borane exists as its dimer, diborane (B2H6), a toxic gas that is inconvenient and hazardous to use. Borane forms stable complexes with ethers, however, and it is often supplied and used as its liquid complex with tetrahydrofuran (THF).Formula: C6H10O2

Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem

Demonstration of Selective Single-Barium Ion Detection with Dry Diazacrown Ether Naphthalimide Turn-on Chemosensors was written by Thapa, Pawan;Byrnes, Nicholas K.;Denisenko, Alena A.;Mao, James X.;McDonald, Austin D.;Newhouse, Charleston A.;Vuong, Thanh T.;Woodruff, Katherine;Nam, Kwangho;Nygren, David R.;Jones, Benjamin J. P.;Foss, Frank W. Jr.. And the article was included in ACS Sensors in 2021.Recommanded Product: 1,4,7,10-Tetraoxa-13-azacyclopentadecane This article mentions the following:

Single-mol. fluorescence imaging (SMFI) of gas-phase ions has been proposed for “barium tagging,” a burgeoning area of research in particle physics to detect individual barium daughter ions. This has potential to significantly enhance the sensitivity of searches for neutrinoless double-beta decay (0νββ) that is obscured by background radiation events. The chem. required to make such sensitive detection of Ba²⁺ by SMFI in dry Xe gas at solid interfaces has implications for solid-phase detection methods but has not been demonstrated. Here, we synthesized simple, robust, and effective Ba²⁺-selective chemosensors capable of function within ultrapure high-pressure ¹³⁶Xe gas. Turn-on fluorescent naphthalimide-(di)azacrown ether chemosensors were Ba²⁺-selective and achieved SMFI in a polyacrylamide matrix. Fluorescence and NMR experiments supported a photoinduced electron transfer mechanism for turn-on sensing. Ba²⁺ selectivity was achieved with computational calculations correctly predicting the fluorescence responses of sensors to barium, mercury, and potassium ions. With these mols., dry-phase single-Ba²⁺ ion imaging with turn-on fluorescence was realized using an oil-free microscopy technique for the first time-a significant advance toward single-Ba²⁺ ion detection within large volumes of ¹³⁶Xe, plausibly enabling a background-independent technique to search for the hypothetical process of 0νββ. In the experiment, the researchers used many compounds, for example, 1,4,7,10-Tetraoxa-13-azacyclopentadecane (cas: 66943-05-3Recommanded Product: 1,4,7,10-Tetraoxa-13-azacyclopentadecane).

1,4,7,10-Tetraoxa-13-azacyclopentadecane (cas: 66943-05-3) belongs to ethers. Relative to alcohols, ethers are generally less dense, are less soluble in water, and have lower boiling points. They are relatively unreactive, and as a result they are useful as solvents for fats, oils, waxes, perfumes, resins, dyes, gums, and hydrocarbons. Vapours of certain ethers are used as insecticides, miticides, and fumigants for soil. At room temperature, ethers are pleasant-smelling colourless liquids. Relative to alcohols, ethers are generally less dense, are less soluble in water, and have lower boiling points. They are relatively unreactive, and as a result they are useful as solvents for fats, oils, waxes, perfumes, resins, dyes, gums, and hydrocarbons. Vapours of certain ethers are used as insecticides, miticides, and fumigants for soil.Recommanded Product: 1,4,7,10-Tetraoxa-13-azacyclopentadecane

Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem

Examination of the Perkin reaction under microwave irradiation was written by Veverkova, E.;Pacherova, E.;Toma, S.. And the article was included in Chemical Papers in 1999.Electric Literature of C11H12O4 This article mentions the following:

The microwave irradiation shortened the reaction time of the Perkin reaction by 60-fold over classical heating. Cesium salts (acetate, carbonate, fluoride) with a small amount of pyridine were found to be the best catalysts under all conditions tested. In the experiment, the researchers used many compounds, for example, 3-(2,4-Dimethoxyphenyl)acrylic acid (cas: 6972-61-8Electric Literature of C11H12O4).

3-(2,4-Dimethoxyphenyl)acrylic acid (cas: 6972-61-8) belongs to ethers. Relative to alcohols, ethers are generally less dense, are less soluble in water, and have lower boiling points. They are relatively unreactive. The unique properties of ethers (i.e., that they are strongly polar, with nonbonding electron pairs but no hydroxyl group) enhance the formation and use of many reagents. For example, Grignard reagents cannot form unless an ether is present to share its lone pair of electrons with the magnesium atom. Complexation of the magnesium atom stabilizes the Grignard reagent and helps to keep it in solution.Electric Literature of C11H12O4

Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem

Natural-product-inspired design and synthesis of thiolated coenzyme Q analogs as promising agents against Gram-positive bacterial strains: insights into structure-activity relationship, activity profile, mode of action, and molecular docking was written by Yildirim, Hatice;Yildiz, Mahmut;Bayrak, Nilufer;Mataraci-Kara, Emel;Ozbek-Celik, Berna;Otsuka, Masami;Fujita, Mikako;Radwan, Mohamed O.;TuYuN, Amac Fatih. And the article was included in RSC Advances in 2022.HPLC of Formula: 605-94-7 This article mentions the following:

In an attempt to develop effective and potentially active antibacterial and/or antifungal agents, we designed, synthesized, and characterized thiolated CoQ analogs (CoQ1-8) with an extensive antimicrobial study. The antimicrobial profile of these analogs was determined using four Gram-neg. bacteria, three Gram-pos. bacteria, and three fungi. Because of the fact that the thiolated CoQ analogs were quite effective on all tested Gram-pos. bacterial strains, including Staphylococcus aureus (ATCC 29213) and Enterococcus faecalis (ATCC 29212), the first two thiolated CoQ analogs emerged as potentially the most desirable ones in this series. Importantly, after the evaluation of the antibacterial and antifungal activity, we presented an initial structure-activity relationship for these CoQ analogs. In addition, the most promising thiolated CoQ analogs (CoQ1 and CoQ2) having the lowest MIC values on all tested Gram-pos. bacterial strains, were further evaluated for their inhibition capacities of biofilm formation after evaluating their in vitro potential antimicrobial activity against each of 20 clin. obtained resistant strains of Gram-pos. bacteria. CoQ1 and CoQ2 exhibited potential mol. interactions with S. aureus DNA gyrase in addition to excellent pharmacokinetics and lead-likeness profiles. Our findings offer important implications for a potential antimicrobial drug candidate, in particular for the treatment of infections caused by clin. resistant MRSA isolates. In the experiment, the researchers used many compounds, for example, 2,3-Dimethoxy-5-methylcyclohexa-2,5-diene-1,4-dione (cas: 605-94-7HPLC of Formula: 605-94-7).

2,3-Dimethoxy-5-methylcyclohexa-2,5-diene-1,4-dione (cas: 605-94-7) belongs to ethers. Relative to alcohols, ethers are generally less dense, are less soluble in water, and have lower boiling points. They are relatively unreactive. Ethers are good solvents partly because they are not very reactive. Most ethers can be cleaved, however, by hydrobromic acid (HBr) to give alkyl bromides or by hydroiodic acid (HI) to give alkyl iodides.HPLC of Formula: 605-94-7

Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem

Polymer-supported dichlorophosphate. A recoverable new reagent for synthesis of 2-amino-1,3,4-thiadiazoles was written by Li, Zheng;Yu, Jin-Lan;Yang, Jing-Ya;Shi, Sheng-Yi;Wang, Xi-Cun. And the article was included in Journal of Chemical Research in 2005.Formula: C9H10O4 This article mentions the following:

Poly(ethylene glycol) (PEG)-supported dichlorophosphate was efficiently used as a recoverable new dehydration reagent for rapid synthesis of 2-amino-5-substituted-1,3,4-thiadiazoles under microwave irradiation and solvent-free condition by reactions of thiosemicarbazide with aliphatic acids, benzoic acid, aryloxy-acetic acids or furan-2-carboxylic acids. In the experiment, the researchers used many compounds, for example, 2-(4-Methoxyphenoxy)acetic acid (cas: 1877-75-4Formula: C9H10O4).

2-(4-Methoxyphenoxy)acetic acid (cas: 1877-75-4) belongs to ethers. Of all the functional groups, ethers are the least reactive ones. Ether bonds are quite stable towards bases, oxidizing agents and reducing agents. Autoxidation is the spontaneous oxidation of a compound in air. In the presence of oxygen, ethers slowly autoxidize to form hydroperoxides and dialkyl peroxides. If concentrated or heated, these peroxides may explode. To prevent such explosions, ethers should be obtained in small quantities, kept in tightly sealed containers, and used promptly.Formula: C9H10O4

Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem

Site-selective [2 + 2 + n] cycloadditions for rapid, scalable access to alkynylated polycyclic aromatic hydrocarbons was written by Kiel, Gavin R.;Bergman, Harrison M.;Tilley, T. Don. And the article was included in Chemical Science in 2020.Quality Control of 1,4-Dimethoxy-2-butyne This article mentions the following:

Here, a general and scalable [2 + 2 + n] (n = 1 or 2) cycloaddition strategy to access polycyclic aromatic hydrocarbons (PAHs) that were decorated with synthetically versatile alkynyl groups and its application to seven structurally diverse PAH ring systems (thirteen new alkynylated PAHs in total) was presented. The critical discovery was the site-selectivity of an Ir-catalyzed [2 + 2 + 2] cycloaddition, which preferentially cyclized tethered diyne units with preservation of other (peripheral) alkynyl groups. The potential for generalization of the site-selectivity to other [2 + 2 + n] reactions was demonstrated by identification of a Cp₂Zr-mediated [2 + 2 + 1]/metallacycle transfer sequence for synthesis of an alkynylated, selenophene-annulated PAH. The new PAHs were excellent synthons for macrocyclic conjugated nanocarbons. As a proof of concept, four were subjected to alkyne metathesis catalysis to afford large, PAH-containing arylene ethylene macrocycles, which possess a range of cavity sizes reaching well into the nanometer regime. Notably, these high-yielding macrocyclizations establish that synthetically convenient pentynyl groups could be effective for metathesis since the 4-octyne byproduct was sequestered by 5 Å MS. Most importantly, this work was a demonstration of how site-selective reactions could be harnessed to rapidly build up structural complexity in a practical, scalable fashion. In the experiment, the researchers used many compounds, for example, 1,4-Dimethoxy-2-butyne (cas: 16356-02-8Quality Control of 1,4-Dimethoxy-2-butyne).

1,4-Dimethoxy-2-butyne (cas: 16356-02-8) belongs to ethers. Of all the functional groups, ethers are the least reactive ones. Ether bonds are quite stable towards bases, oxidizing agents and reducing agents. Ethyl ether is an excellent solvent for extractions and for a wide variety of chemical reactions. It is also used as a volatile starting fluid for diesel engines and gasoline engines in cold weather. Dimethyl ether is used as a spray propellant and refrigerant. Methyl t-butyl ether (MTBE) is a gasoline additive that boosts the octane number and reduces the amount of nitrogen-oxide pollutants in the exhaust. The ethers of ethylene glycol are used as solvents and plasticizers.Quality Control of 1,4-Dimethoxy-2-butyne

Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem