Category: benzothiophene

Investigation of the limit of discovery using tile-based Fisher ratio analysis with comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry was written by Sudol, Paige E.;Ochoa, Grant S.;Synovec, Robert E.. And the article was included in Journal of Chromatography A in 2021.Electric Literature of C6H8S The following contents are mentioned in the article:

Comprehensive two-dimensional gas chromatog. coupled with time-of-flight mass spectrometry (GCxGC-TOFMS) is followed by tile-based Fisher ratio (F-ratio) anal. to investigate the “limit of discovery” for low concentration levels of sulfur-containing compounds in JP8 jet fuel. A mixture of 14 sulfur-containing compounds was spiked at 30 ppm, 15 ppm, 3 ppm and 1.5 ppm into the neat fuel prior to GCxGC-TOFMS anal. with a “reversed” column format (aka polar first dimension (1D) and non-polar second dimension (2D) column). Prior standard implementation of tile-based F-ratio anal. utilized an average F-ratio requiring a min. of 3 mass channels (m/z) with the highest F-ratios. Herein, we explore the notion that use of the top F-ratio m/z for hitlist ranking is superior to the standard implementation for analytes near their limit-of-quantitation (LOQ), defined as an analyte concentration that produces a signal equal to ten times the standard deviation of the baseline noise (10σn). Hitlist ranking comparisons revealed that using only the top F-ratio m/z resulted in impressive improvements in discoverability for the low concentration comparisons. Specifically, for the 3 ppm vs. neat hitlist, 1,4-oxathiane (LOQ = 2.5 ppm) improved from hit 114 via standard F-ratio anal., to hit 25. For the 1.5 ppm vs. neat hitlist, 2-propylthiophene (LOQ = 0.64 ppm) improved from hit 59 to 17, benzo[b]thiophene (LOQ = 1.1 ppm) from hit 98 to 28, and 2,5-dimethylthiophene (LOQ = 1.3 ppm) from hit 262 to 39. Addnl. hitlist ranking comparisons revealed the importance of proper tile size selection, as analyte discoverability deteriorated upon using either an inappropriately too small or too large of a tile. This study involved multiple reactions and reactants, such as 2,5-Dimethylthiophene (cas: 638-02-8Electric Literature of C6H8S).

2,5-Dimethylthiophene (cas: 638-02-8) belongs to benzothiophene derivatives. Benzothiophene is relatively a stable molecule. The electrophilic substitution of benzothiophene systems is much less regioselective than that of indoles. It is found within the chemical structures of pharmaceutical drugs such as raloxifene, zileuton, sertaconazole, and also BTCP.Electric Literature of C6H8S

Referemce:
Benzothiophene – Wikipedia,
Benzothiophene | C8H6S – PubChem

Non-Oxido-Vanadium(IV) Metalloradical Complexes with Bidentate 1,2-Dithienylethene Ligands: Observation of Reversible Cyclization of the Ligand Scaffold in Solution was written by Schlueter, Dirk;Kleemiss, Florian;Fugel, Malte;Lork, Enno;Sugimoto, Kunihisa;Grabowsky, Simon;Harmer, Jeffrey R.;Vogt, Matthias. And the article was included in Chemistry – A European Journal in 2020.Computed Properties of C6H8S The following contents are mentioned in the article:

Derivatives of 1,2-dithienylethene (DTE) have superb photochromic properties due to an efficient reversible photocyclization reaction of their hexatriene structure and, thus, have application potential in materials for optoelectronics and (multi-responsive) mol. switches. Transition-metal complexes bearing switchable DTE motifs commonly incorporate their coordination site rather distant from the hexatriene system. The redox active ligand 1,2-bis(2,5-dimethylthiophen-3-yl)ethane-1,2-dione is described, which reacts with [V(TMEDA)₂Cl₂] to give a rare non-oxido vanadium(IV) species 3(M,M/P,P). This blue complex has two bidentate en-diolato ligands which chelate the V^IV center and give rise to two five-membered metallacycles with the adjacent hexatriene DTE backbone bearing axial chirality. Upon irradiation with UVA light or prolonged heating in solution, the blue compound 3(M,M/P,P) converts into the purple atropisomer 4(para,M/para,P). Both complexes were isolated and structurally characterized by single-crystal x-ray diffraction anal. (using lab source and synchrotron radiation). The antiparallel configuration (M or P helicity) present in both 3(M,M/P,P) and 4(para,M/para,P) is a prerequisite for (reversible) 6π cyclization reactions. A continuous-wave EPR spectroscopic study reveals the metalloradical character for 3(M,M/P,P) and 4(para,M/para,P) and indicates dynamic reversible cyclization of the DTE backbone in complex 3(M,M/P,P) at ambient temperature in solution This study involved multiple reactions and reactants, such as 2,5-Dimethylthiophene (cas: 638-02-8Computed Properties of C6H8S).

2,5-Dimethylthiophene (cas: 638-02-8) belongs to benzothiophene derivatives. Benzothiophene finds use in research as a starting material for the synthesis of larger, usually bioactive structures. It has been used as a raw material for the synthesis of biologically active structures and is found in pharmaceuticals such as leukotriene synthesis inhibitors and antifungals, as well as in many natural products.Computed Properties of C6H8S

Referemce:
Benzothiophene – Wikipedia,
Benzothiophene | C8H6S – PubChem

Time-Resolved Photoelectron Studies of Thiophene and 2,5-Dimethylthiophene was written by Schalk, O.;Larsen, M. A. B.;Skov, A. B.;Liisberg, M. B.;Geng, T.;Soelling, T. I.;Thomas, R. D.. And the article was included in Journal of Physical Chemistry A in 2018.Quality Control of 2,5-Dimethylthiophene The following contents are mentioned in the article:

The photoinduced dynamics of thiophene and 2,5-dimethylthiophene (2,5-DMT) were investigated upon excitation at 200 and 255 nm (2,5-DMT only) using time-resolved photoelectron spectroscopy and compared with results from ab initio coupled cluster calculations For thiophene, depopulation of the initially excited B₂(π₃π₄*) state to the lower-lying A₁(π₂π₄*) state occurs within 25 ± 20 fs, with a subsequent bifurcation into a ring-puckering channel and a ring-opening channel with lifetimes of 80 ± 20 and 450 ± 50 fs, resp. For 2,5-DMT, the dynamics following excitation at 200 nm is described by a monoexponential decay with a time constant of 120 ± 20 fs, while that following excitation at 255 nm is best fit by a biexponential decay with time constants of 115 ± 20 fs and 15 ± 3 ps, resp. The fast signal observed after excitation of 2,5-DMT is assigned to the ring-opening channel, which is favored with respect to thiophene due to a lower excited-state barrier along the ring-opening coordinate and an increased inertia toward the ring-puckering channel. Coupled cluster calculations have been undertaken to compare the relaxation dynamics of thiophene to thiazole and isothiazole. For the latter two mols., we find a strong gradient along the ring-opening coordinate in the Franck-Condon region of the initially populated ππ* state and predict that ring-opening is the dominating relaxation channel after photoexcitation. We use the extracted information for a comparison of the thiophene dynamics with the light-induced processes observed in other five-membered heterocyclic mols. This study involved multiple reactions and reactants, such as 2,5-Dimethylthiophene (cas: 638-02-8Quality Control of 2,5-Dimethylthiophene).

2,5-Dimethylthiophene (cas: 638-02-8) belongs to benzothiophene derivatives. Benzothiophene is relatively a stable molecule. The core structure is a part of various pharmaceutical substances and natural products. The different substitution patterns in these heterocycles offer new opportunities for drug discovery and other applications in materials science.Quality Control of 2,5-Dimethylthiophene

Referemce:
Benzothiophene – Wikipedia,
Benzothiophene | C8H6S – PubChem

Comprehensive Three-Dimensional Gas Chromatography with Time-of-Flight Mass Spectrometry was written by Watson, Nathanial E.;Bahaghighat, H. Daniel;Cui, Ke;Synovec, Robert E.. And the article was included in Analytical Chemistry (Washington, DC, United States) in 2017.COA of Formula: C6H8S The following contents are mentioned in the article:

Development of comprehensive, three-dimensional (3D) gas chromatog. with time-of-flight mass spectrometric detection (GC³/TOFMS) is described. This instrument provides four dimensions (4D) of chem. selectivity and includes significant improvements to total selectivity (mass spectrometric and chromatog.), peak identification, and operational temperature range relative to previous models of the GC³ reported. The new instrumental design and data output are evaluated and illustrated via two samples, a 115-component test mixture and a diesel fuel spiked with several compounds, for the purpose of illustrating the chem. selectivity benefits of this instrumental platform. Useful approaches to visualize the 4-dimensional data are presented. The GC³/TOFMS instrument exptl. achieved total peak capacity, n_c,3D, ranging from 5000 to 9600 (x̅ = 7000, s = 1700) for 10 representative analytes for 50 min separations with component dimensional peak capacities averaging 406, 3.6, and 4.9 for ¹D, ²D, and ³D, resp. Particularly, GC³/TOFMS achieved a combined ²D × ³D peak capacity ranging from 10 to 26 (x̅ = 17.6, s = 5.0), which is similar to what is achieved by ²D alone in a GC × GC operating at equivalent modulation period conditions. The anal. benefits of employing three varied chem. selectivities in the 3-dimensional separation coupled with TOFMS are illustrated through the separation and detection of 1,6-dichlorohexane and cyclohexyl isothiocyanate as part of the diesel fuel anal. This study involved multiple reactions and reactants, such as 2,5-Dimethylthiophene (cas: 638-02-8COA of Formula: C6H8S).

2,5-Dimethylthiophene (cas: 638-02-8) belongs to benzothiophene derivatives. Benzothiophene scaffolds are of great importance due to its increased presence in bioactive molecules. Its aromaticity makes it relatively stable, although as a heterocycle, it has reactive sites which allow for functionalization.COA of Formula: C6H8S

Referemce:
Benzothiophene – Wikipedia,
Benzothiophene | C8H6S – PubChem

Analysis of pollutants in the product gas of a pilot scale downdraft gasifier fed with wood, or mixtures of wood and waste materials was written by Vonk, G.;Piriou, B.;Wolbert, D.;Cammarano, C.;Vaitilingom, G.. And the article was included in Biomass and Bioenergy in 2019.Category: benzothiophene The following contents are mentioned in the article:

Small scale gasification of Solid Recovered Fuels (SRF) in downdraft reactors could be an alternative to large scale waste-to-energy schemes. In this perspective, the assessment of the pollutant emissions at pilot scale is necessary. This work compares pollutant emissions from wood and SRF air gasification in a downdraft fixed bed gasifier. Five fuels have been studied: Poplar wood, SRF wood, and three different mixtures containing mass fractions of 80% SRF wood with 20% of either tire, plastic waste or sewage sludge. Air gasification was performed in a pilot scale reactor in fed-batch mode using a fuel mass ranging from 5 to 8 kg and an air inlet flow of 170-180 L min^-1 (at 0°C and 101 325 Pa). Depending on the fuel, Equivalence Ratios (ER) ranged from 0.22 to 0.29 and gasification temperatures from 690 to 850°C. Emissions analyses were performed on product gas, condensable species and remaining chars, with a particular focus on sulfur, nitrogen and heavy metals. Regarding sulfur, wood and SRF wood led to low H₂S contents (6-8μmol mol^-1), when SRF mixes led to higher concentrations (44-96μmol mol^-1) in addition to of up to 11 heavier sulfur compounds Regarding nitrogen, SRF produced higher ammonia concentrations (2.1-7.6 mmol mol^-1) than Wood (619μmol mol^-1), as a result of initial nitrogen mass fractions17 to 27 times higher in the SRF mixes. Heavy metals analyzed in remaining solids after gasification showed low recovery rates (<0.4%), and tend to accumulate in fine particles, as a result of their volatility. This study involved multiple reactions and reactants, such as 2,5-Dimethylthiophene (cas: 638-02-8Category: benzothiophene).

2,5-Dimethylthiophene (cas: 638-02-8) belongs to benzothiophene derivatives. Benzothiophene is relatively a stable molecule. The core structure is a part of various pharmaceutical substances and natural products. Its aromaticity makes it relatively stable, although as a heterocycle, it has reactive sites which allow for functionalization.Category: benzothiophene

Referemce:
Benzothiophene – Wikipedia,
Benzothiophene | C8H6S – PubChem