Author: Jessica.F

Cakar, Ayse Erdogan published the artcileDetermination of the surface thermodynamic characteristics and the structural isomer separation ability of new synthesized phenylbenzoate-based three-ring calamitic liquid crystals by inverse gas chromatography, HPLC of Formula: 143-15-7, the publication is Journal of Molecular Structure (2022), 133379, database is CAplus.

Two different new calamitic liquid crystals (LCs), 4-[4-(((S)-3,7-dimethyloctyloxy)phenoxy)carbonyl]phenyl 4-(n-decyloxy)benzoate (DPDEB) and 4-[4-(((S)-3,7-dimethyloctyloxy)phenoxy)carbonyl]phenyl 4-(n-dodecyloxy)benzoate (DPDOB) were synthesized and characterized using ¹H-NMR, and ¹³C-NMR. The LC behavior of the target compounds was investigated by optical polarization microscopy (PM) and differential scanning calorimetry (DSC). The selectivity coefficients, a, of the structural isomers at infinite dilution for the DPDEB and DPDOB LCs were determined for Bu acetate, Bu alc. and amyl alc. isomers. Surface energy anal. has been performed using inverse gas chromatog. (IGC). By using suitable solvents, the surface properties and separation power of isomers of DPDEB and DPDOB LCs were determined between 303.2 and 323.2 K. Experiments with LC’s have been conducted at infinite dilution to the specific adsorption enthalpy and the specific adsorption free energy. IGC measurements exhibited values of acidity constants (K_A) of 0.033 and 0.057 and basic constants (K_D) of 0.176 and 0.242 for DPDEB and DPDOB, resp. It has been found that all LCs show basic character.

Journal of Molecular Structure published new progress about 143-15-7. 143-15-7 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 1-Bromododecane, and the molecular formula is C12H25Br, HPLC of Formula: 143-15-7.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Fan, Ye published the artcileReversible-Tuning Krafft Temperature of Selenium-Containing Ionic Surfactants by Redox Chemistry, Computed Properties of 55788-44-8, the publication is Langmuir (2020), 36(13), 3514-3521, database is CAplus and MEDLINE.

An easy, effective, and reversible strategy for tuning the Krafft temperature (K_T) of selenium-containing ionic surfactants, with head groups ranging in nature from anionic to amphoteric, has been achieved for the first time via the redox chem. of selenium. After oxidation with H₂O₂, the selenide group was converted to a more hydrophilic selenoxide group. This made the oxidized forms of the surfactants more water-soluble, which results in a marked reduction in the K_T. In contrast, the hydrophilic selenoxide was restored to its reduced form of selenide via reduction reaction, which allowed the K_T value to return to its initial value. By alternating the oxidization and reduction treatments, the K_T of the selenium-containing surfactants in this work could be reversibly switched over 5-10 cycles without causing obvious adverse distortions.

Langmuir published new progress about 55788-44-8. 55788-44-8 belongs to bromides-buliding-blocks, auxiliary class Bromide,Salt,Aliphatic hydrocarbon chain,Aliphatic hydrocarbon chain, name is Sodium 3-bromopropane-1-sulfonate, and the molecular formula is C3H6BrNaO3S, Computed Properties of 55788-44-8.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Satz, Alexander Lee published the artcileDNA Compatible Multistep Synthesis and Applications to DNA Encoded Libraries, Formula: C9H7BrF3NO2, the publication is Bioconjugate Chemistry (2015), 26(8), 1623-1632, database is CAplus and MEDLINE.

Complex mixtures of DNA encoded small mols. may be readily interrogated via high-throughput sequencing. These DNA encoded libraries (DELs) are commonly used to discover mols. that interact with pharmaceutically relevant proteins. The chem. diversity displayed by the library is key to successful discovery of potent, novel, and drug-like chem. matter. The small mol. moieties of DELs are generally synthesized though a multistep process, and each chem. step is accomplished while it is simultaneously attached to an encoding DNA oligomer. Hence, library chem. diversity is often limited to DNA compatible synthetic reactions. Herein, protocols for 24 reactions are provided that have been optimized for high-throughput production of DELs. These protocols detail the multistep synthesis of benzimidazoles, imidazolidinones, quinazolinones, isoindolinones, thiazoles, and imidazopyridines. Addnl., protocols are provided for a diverse range of useful chem. reactions including BOC deprotection (under pH neutral conditions), carbamylation, and Sonogashira coupling. Last, step-by-step protocols for synthesizing functionalized DELs from trichloronitropyrimidine and trichloropyrimidine scaffolds are detailed.

Bioconjugate Chemistry published new progress about 1260672-86-3. 1260672-86-3 belongs to bromides-buliding-blocks, auxiliary class Trifluoromethylated Building Blocks, name is Methyl 2-(bromomethyl)-5-(trifluoromethyl)nicotinate, and the molecular formula is C9H7BrF3NO2, Formula: C9H7BrF3NO2.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Oncu, Aysegul published the artcileSynthesis of methylthionaphthalene derivatives, Name: 1,3-Dibromonaphthalene, the publication is Turkish Journal of Chemistry (2006), 30(2), 235-241, database is CAplus.

A new and convenient method was developed for the synthesis of methylthio naphthalene derivatives from corresponding bromonaphthalenes by treatment with t-BuLi followed by di-Me disulfide. 2-(Methylthio)naphthalene, 1,3-bis(methylthio)naphthalene, 1,4-bis(methylthio)naphthalene, 1,5-bis(methylthio)naphthalene, and 1,3,5-tris(methylthio)naphthalene were obtained.

Turkish Journal of Chemistry published new progress about 52358-73-3. 52358-73-3 belongs to bromides-buliding-blocks, auxiliary class Bromide,Naphthalene, name is 1,3-Dibromonaphthalene, and the molecular formula is C10H6Br2, Name: 1,3-Dibromonaphthalene.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Nelson, David A. published the artcileUse of fluorescent 1,3-disubstituted 2(1H)-pyridones for environmental analysis, Category: bromides-buliding-blocks, the publication is ACS Symposium Series (1989), 383(Lumin. Appl. Biol.), 206-27, database is CAplus.

Fluorescent derivatives were prepared from a series of alkyl halides and alcs. using derivatizing reagents prepared from 3-carbamoyl-2(1H)-pyridone and 3-phenyl-2(1H)-pyridone. These derivatives were designed to be analyzed by HPLC using fluorescence detection, and they could be measured at the picomole level. The derivatization chem. is applicable to a wide variety of organic compounds Derivatives were also prepared from amines, phenols, acrylonitrile, and heptachlor. A series of 6 pyridonesulfonates was synthesized for use as fluorescent, site-specific, water-tracing compounds

ACS Symposium Series published new progress about 55788-44-8. 55788-44-8 belongs to bromides-buliding-blocks, auxiliary class Bromide,Salt,Aliphatic hydrocarbon chain,Aliphatic hydrocarbon chain, name is Sodium 3-bromopropane-1-sulfonate, and the molecular formula is C3H6BrNaO3S, Category: bromides-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Pardo-Rodriguez, Virtudes published the artcilePd-catalyzed borylative cyclisation of 1,7-enynes, HPLC of Formula: 69361-41-7, the publication is Chemical Communications (Cambridge, United Kingdom) (2012), 48(85), 10517-10519, database is CAplus and MEDLINE.

A variety of 1,7-enynes undergo nucleophilic boration and cyclization with bis(pinacolato)diboron catalyzed by Pd bis(trifluoroacetate), affording alkylidenecyclohexane-substituted homoallylic and allylic boronates by formation of C-C and C-B bonds. Reaction of CR³R⁴:CR²CH₂XYCH₂CCR¹ [X = C(CO₂Me)₂, C(SO₂Ph)₂, Y = CH₂; X = CH₂, Y = C(CO₂Me)₂, NTs] with pin₂B₂, catalyzed by Pd(TFA)₂ gave methylenecyclohexanes I (2a–i, 4a–h, R¹ = H, Me, Ph, TMS; R²-R⁴ = H, Me, CH₂OAc) together with cyclohexenylmethyl boronates II [5, Y = C(CO₂Me)₂, NTs]. The reaction mechanism comprises palladium addition to the triple bond with subsequent formation of palladaindene and elimination; the compounds 5 were rationalized as products of palladium-catalyzed isomerization of 4.

Chemical Communications (Cambridge, United Kingdom) published new progress about 69361-41-7. 69361-41-7 belongs to bromides-buliding-blocks, auxiliary class PROTAC Linker,Aliphatic Linker, name is (4-Bromobut-1-yn-1-yl)trimethylsilane, and the molecular formula is C7H13BrSi, HPLC of Formula: 69361-41-7.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Rowland, Stanley P. published the artcileReagent effects on distribution of methylsulfonylethyl substituents in the D-glucopyranosyl unit of cotton cellulose, Recommanded Product: 2-Bromoethyl Methyl Sulfone, the publication is Canadian Journal of Chemistry (1968), 46(3), 451-7, database is CAplus.

The distribution of methylsulfonylethyl substituents at the 2-O-, 3-O-, and 6-O-positions of the monosubstituted D-glucopyranosyl unit of cotton cellulose is a function of the specific reagent and the reaction conditions. The distribution is dependent upon the extent to which rate or equilibrium of reaction at the individual hydroxyl groups is the controlling factor. Under conditions which approach equilibrium in the reaction of methyl vinyl sulfone with cotton cellulose, the ratio of 2-O- to 6-O-substitution is 0.14:1.0. A variety of precursors for methyl vinyl sulfone [2-(methylsulfonyl)ethanol, [2-(methyl-sulfonyl)ethyl]pyridinium chloride, 2-bromoethyl methyl sulfone, and bis-[2-(methylsulfonyl) ethyl] ether] react with cotton cellulose under nonequilibrium conditions to generate ratios of 2-O- to 6-O-substitutions as high as 0.44:1.0. The effect of diffusion of reagents into the cotton fiber upon the distribution of substituents is clearly evident in these reactions. Specific modifications of the process of reaction of methyl vinyl sulfone or 2-(methylsulfonyl)ethanol with cotton cellulose yield ratios of substituents in the 2-O- to 6-O-positions as high as 0.8:1.0; this ratio is similar to those which characterize certain rate-controlled Williamson etherification reactions with cotton cellulose. 21 references.

Canadian Journal of Chemistry published new progress about 16523-02-7. 16523-02-7 belongs to bromides-buliding-blocks, auxiliary class Bromide,Sulfone,Aliphatic hydrocarbon chain, name is 2-Bromoethyl Methyl Sulfone, and the molecular formula is C3H7BrO2S, Recommanded Product: 2-Bromoethyl Methyl Sulfone.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Davies, Jonathan A. published the artcileTotal synthesis of Kalimantacin A, Application In Synthesis of 69361-41-7, the publication is Organic Letters (2020), 22(16), 6349-6353, database is CAplus and MEDLINE.

The kalimantacins make up a family of hybrid polyketide-nonribosomal peptide-derived natural products that display potent and selective antibiotic activity against multidrug resistant strains of Staphylococcus aureus. Herein, we report the first total synthesis of kalimantacin A, in which three fragments are prepared and then united via Sonogashira and amide couplings. The enantioselective synthetic approach is convergent, unlocking routes to further kalimantacins and analogs for structure-activity relationship studies and clin. evaluation.

Organic Letters published new progress about 69361-41-7. 69361-41-7 belongs to bromides-buliding-blocks, auxiliary class PROTAC Linker,Aliphatic Linker, name is (4-Bromobut-1-yn-1-yl)trimethylsilane, and the molecular formula is C7H13BrSi, Application In Synthesis of 69361-41-7.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Russell, Glen A. published the artcileDirective effects in aliphatic substitutions. III. The photobromination of branched-chain hydrocarbons; the dark reaction of bromine with tertiary alkyl bromides, Recommanded Product: 2,3-Dibromo-2,3-dimethylbutane, the publication is Journal of the American Chemical Society (1955), 4025-30, database is CAplus.

The photobromination of hydrocarbons in the liquid phase is highly selective and constitutes an excellent method for the preparation of tertiary bromides from hydrocarbons which contain only primary and tertiary H atoms. The presence of secondary or an addnl. tertiary H atom in the adjacent position leads to the formation of considerable amounts of dibromides. It is proposed that these dibromides arise from an ionic or mol. reaction of Br with the tertiary bromide formed in the initial photochem. reaction. The dark reaction of Br with Me₃CBr exhibits 3rd order kinetics. No evidence could be obtained of a measurable equilibrium between olefin and hydrogen halide in solutions of Me₃CBr and Me₃CCl in refluxing SO₂ or of Me₂CBrCMe₃ (XVII) in CCl₄ at 76°. Yet Br reacts rapidly with the tertiary halides under these conditions. These results are consistent with a reaction mechanism in which a Br mol. brings about the ionization of the tertiary bromide, followed by reaction of a 2nd Br mol. with the high-energy π-complex form of the carbonium ion. Me₃CCHMe₂ (XVIII), b₇₄₅ 80.3°, n_D²⁰ 1.3895 (1 mol) irradiated with a 150-w. clear light bulb (1 in. from the flask) and treated 1.5 h. with 0.25 mol Br at 80°, 25 g. XVIII distilled off, the residue cooled, and the nearly solid crystalline mass (57 g.) washed with 50 cc. cold XVIII gave 36 g. XVII, m. 149-50° (sealed tube), and 10 g. XVIII by vacuum sublimation at 80°/25 mm. Cumene (XIX) (1 mol), b₇₄₀ 151.4-5°, n_D²⁰ 1.4915, brominated similarly 0.5 h. with 0.5 mol Br at 60°, and the mixture bubbled with N to remove the HBr and analyzed for total and hydrolyzable Br (80% EtOH at 25°) showed that 73% of the Br was present as the tertiary bromide. A similar run with 0.25 mol Br/mol XIX gave during 1.5 h. at 0° a product containing 94% of the Br as tertiary bromide; the bromide could not be crystallized from the solution at -80° and attempts to distil below 1 mm. resulted in dehydrobromination. Br (0.5 mol) added under illumination to 0.5 mol XIX in CH₂Cl₂ at 0° until the Br color persisted 2 min. after the addition of 1 drop Br and the product rectified gave 111 g. MePhCBrCH₂Br, b₁₆ 120-20.5°. Br (0.5 mol) added to 2 mol (Me₂CH)₂ (XX), n_D²⁰ 1.3749, at 55° during 6 h. at such a rate that the hydrocarbon remained colorless through the reaction, the mixture cooled, and the crystalline deposit (65 g.) sublimed at 95-100°/5 mm. gave 54 g. (Me₂CBr)₂ (XXI), m. 169-71° (sealed tube). Br (0.5 mol) added dropwise at 60° during 8 h. to 2 mol Me₂CHPr (XXII), n_D²⁰ 1.3714, at such a rate that the solution was nearly colorless at all times, and the mixture fractionated gave 64 g. mixture of 92% Me₂CHBrPr and 8% secondary bromides from XXII, and 10 g. material, b₄₀ 92-2.5°, containing 64.5% Br, largely as Me₂CBrCHBrEt. XVII (0.075 mol) in 100 g. CCl₄ treated 40 h. at 25° with 0.076 mol dry Br, the CCl₄ removed, the mixture sublimed in vacuo to remove 2 g. unchanged XVII, and the residue distilled gave 10.3 g. dibromide, b₁₀ 88.5-9.5°, presumably BrCH₂CMeBrCMe₃, and 3 g. tribromides, b₃ 107-10°. Br (0.25 mol) and 0.25 mol Me₂CBrEt in 120 cc. CCl₄ held 40 h. at 25° in the dark and the mixture distilled gave 34 g. Me₂CBrCHBrMe, b₃₀ 72.5-73°, n_D²⁰ 1.5095, and 8.5 g. tribromide, b₁₅ 110-14°. Me₂C(OH)CHMe₂ (XXIII), b₁₀₀ 65.5, n_D²⁰ 1.4182, (10.2 g.) as a 2M solution in CCl₄ treated with Br 60 h. in the dark and the product crystallized and rectified gave 18.2 g. XXI, m. 168-9°, 2.1 g. unchanged XXIII, 1 g. tribromide, b₂₅ 140-50°, and traces of a lachrymator. A similar run with 16 g. Br and 10.2 g. XXIII in the presence of 10 g. finely divided CaCO₃ showed only 80% reaction of the Br in 72 h. and gave 10 g. dibromide, 5 g. XXIII, and 4 g. high-boiling material, presumably a tribromide. Me₃CBr (40 g.) and 46 g. Br held 42 h. at 0° in the dark and the mixture distilled gave 43 g. Me₂CBrCH₂Br, b. 146-9°, and 6 g. higher-boiling material, probably the tribromide. Br (15.984 and 13.700 g. Me₃CBr diluted to 100 cc. at 0° with CCl₄, 5-cc. samples sealed in ampuls, stored in ice, and 1-cc. aliquots titrated with standard Na₂S₂O₃ at appropriate intervals gave the kinetic data for the bromination; average k₃ × 10² l.²/mol²/h. 0.52. Photobrominations at 25° were carried out with 5 mol % solutions by degassing the appropriate hydrocarbon with N, vaporizing dry Br in a stream of N, passing the Br-N mixture during 1 h. into the hydrocarbon, removing the HBr with N, and analyzing the mixture (the Br used, the total bromide, and the tertiary bromide, all in moles, given): XIX, 0.055, 0.0541, 0.0541; XVIII, 0.050, 0.0486, 0.0457; XXII, 0.051, 0.0492, 0.0443; XX, 0.051, -, 0.0214 (some dibromide crystallized during the bromination); XX, 0.031, 0.0302, 0.0238; XX (0°), 0.038, 0.0371, 0.0326. Me₃CCl (5 cc.) added during 6 h. to 15 cc. SO₂ refluxing at -12.5 ± 0.5°, and 100 cc. vapor removed under standard conditions and analyzed in a mass spectrometer showed that not more than 0.001% Me₃CCl had been dehydrochlorinated. Me₃CBr (5 g.) treated 6 h. with 25 cc. SO₂ refluxing at -14 ± 0.5°/722 mm. was less than 0.001% dehydrobrominated. XVII (500 cc. 0.2M solution in CCl₄) rectified at atm. pressure, 400 cc. CCl₄ removed during 24 h., all gases formed passed into aqueous NaOH, and the distillate extracted with H₂O indicated the complete absence of acidic materials or bromide ion. Me₂CBrEt (5 cc.), 25 cc. CH₂Cl₂, and 2 g. iodine refluxed at such a pressure that the temperature was 25°, and 100 cc. vapor removed under a high reflux ratio during 6 h. and analyzed showed less than 0.001% dehydrobromination.

Journal of the American Chemical Society published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Recommanded Product: 2,3-Dibromo-2,3-dimethylbutane.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Gruijters, Bas W. T. published the artcileCatalyst Recycling via Hydrogen-Bonding-Based Affinity Tags, Application In Synthesis of 25753-84-8, the publication is Organic Letters (2006), 8(15), 3163-3166, database is CAplus and MEDLINE.

A novel procedure for catalyst recycling is described. Copper(I)-based catalysts, equipped with an affinity tag, are isolated from crude reaction mixtures on the basis of quadruple hydrogen-bonding interactions using a resin functionalized with complementary affinity tags. Recycled catalysts were successfully used to catalyze a tandem Sonogashira coupling/5-endo-dig cyclization and a Cu-catalyzed [3+2] Huisgen cycloaddition reaction in high yields.

Organic Letters published new progress about 25753-84-8. 25753-84-8 belongs to bromides-buliding-blocks, auxiliary class Copper, name is Bromo(1,10-phenanthroline)(triphenylphosphine)copper(I), and the molecular formula is C30H24BrCuN2P, Application In Synthesis of 25753-84-8.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary