Month: December 2022

Richard, Marcia E. published the artcileProbing the steric limits of rhodium catalyzed hydrophosphinylation. P-H addition vs. dimerization/oligomerization/polymerization, Safety of Dimesitylphosphine oxide, the publication is Journal of Organometallic Chemistry (2010), 696(1), 123-129, database is CAplus.

The reactivity of secondary phosphine oxides containing bulky organic fragments in hydrophosphinylation reactions has been investigated using several rhodium based catalysts. Upon heating in a focused microwave reactor, HP(O)(2-C₆H₄Me)₂ adds to prototypical terminal alkynes affording a complex mixture containing 1,2 and 1,1-addition products. Addition of a second ortho-substituent (HP(O)Mes₂) completely suppresses the hydrophosphinylation reaction for alkyl and aryl substituted alkynes. Variations in the temperature, catalyst loading, solvent, and microwave power were unable to induce an addition reaction in the case of HP(O)Mes₂. While this secondary phosphine oxide did not participate in the hydrophosphinylation reaction, it promoted the polymerization of phenylacetylene. HP(O)R₂ substrates are not commonly thought of as innocent ligands for rhodium complexes in reactions involving alkynes due to facile hydrophosphinylation. While this is certainly true for diphenylphosphine oxide, the chem. presented herein suggests that HP(O)Mes₂ and related bulky secondary phosphine oxides have great potential as valuable ligands for rhodium catalyzed transformations involving alkynes due to their lack of reactivity towards the addition reaction.

Journal of Organometallic Chemistry published new progress about 23897-16-7. 23897-16-7 belongs to catalysis-chemistry, auxiliary class Aryl phosphine ligand,Mono-phosphine Ligands, name is Dimesitylphosphine oxide, and the molecular formula is C18H23OP, Safety of Dimesitylphosphine oxide.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Kalinin, Alexey V. published the artcileSynthesis of Constrained Raloxifene Analogues by Complementary Use of Friedel-Crafts and Directed Remote Metalation Reactions, Computed Properties of 6972-05-0, the publication is Journal of Organic Chemistry (2003), 68(15), 5992-5999, database is CAplus and MEDLINE.

New constrained heterocyclic analogs of Raloxifene, I [R¹ = 2-(1-piperidinyl)ethoxy, R² = H; R¹ = H, R² = 2-(1-piperidinyl)ethoxy] and II, were prepared by complementary Directed remote Metalation (DreM)/Friedel-Crafts cyclization approaches. Utilization of a benzylidene-thiolactone rearrangement was successfully implemented to construct benzothiophenes III (R³ = Me₂CH, R⁴ = MeO; R³ = Me, PhCH₂, R⁴ = Et₂N) in good yields. Selective deprotection of III (R³ = Me₂CH, R⁴ = MeO; R³ = PhCH₂, R⁴ = Et₂N) induced by complexation was followed by trifluoromethylsulfonylation and Suzuki-Miyaura cross coupling with 3-[2-(1-piperidinyl)ethoxy]phenyl dioxaborolane to give the corresponding 2,4-diaryl-substituted benzothiophenes with methoxycarbonyl or diethylcarbamoyl group in the 3 position. Treatment of the latter with BCl₃ or with excess LDA induced an intramol. para or ortho cyclization and concomitant double deprotection to furnish I. Similar sequence starting from III (R³ = Me, R⁴ = Et₂N) afforded the constrained analog II.

Journal of Organic Chemistry published new progress about 6972-05-0. 6972-05-0 belongs to catalysis-chemistry, auxiliary class Thiourea,Amine,Aliphatic hydrocarbon chain,Amide, name is 1,1-Dimethylthiourea, and the molecular formula is C3H8N2S, Computed Properties of 6972-05-0.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Reddy, N. Koteswara published the artcileThe structural behavior of layers of SnS grown by spray pyrolysis, Formula: C3H8N2S, the publication is Journal of Physics D: Applied Physics (1999), 32(9), 988-990, database is CAplus.

Thin layers of SnS were grown from equimolar solutions of Sn chloride and N,N-dimethylthiourea on Corning 7059 glass substrates at various temperatures in the range 100-450¡ã using spray pyrolysis. The structural properties were determined by using x-ray diffraction and SEM to evaluate the crystalline phases present and the surface topog. of the grown layers. The changes observed in the structural phases with the growth temperature during the film formation are reported and discussed.

Journal of Physics D: Applied Physics published new progress about 6972-05-0. 6972-05-0 belongs to catalysis-chemistry, auxiliary class Thiourea,Amine,Aliphatic hydrocarbon chain,Amide, name is 1,1-Dimethylthiourea, and the molecular formula is C3H8N2S, Formula: C3H8N2S.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Reddy, N. Koteeswara published the artcileElectrical properties of spray pyrolytic tin sulfide films, Application of 1,1-Dimethylthiourea, the publication is Solid-State Electronics (2005), 49(6), 902-906, database is CAplus.

Tin sulfide (Sn_xS_y) films were prepared using spray pyrolysis technique at different substrate temperatures (T_s), (100-450¡ãC) on Corning 7059 glass substrates. The phys. parameters such as elec. resistivity, Hall mobility and net carrier d. of the films were determined at room temperature The films grown in the substrate temperature range, 300-375¡ãC, were found to be p-type conducting. These SnS films showed average elec. resistivity of ?30 ¦¸ cm, Hall mobility of ?130 cm²/V s and carrier d., >10¹⁵ cm^-3. The temperature dependence of elec. conductivity of the films was also studied and the activation energies evaluated. The results obtained were discussed and reported.

Solid-State Electronics published new progress about 6972-05-0. 6972-05-0 belongs to catalysis-chemistry, auxiliary class Thiourea,Amine,Aliphatic hydrocarbon chain,Amide, name is 1,1-Dimethylthiourea, and the molecular formula is C3H8N2S, Application of 1,1-Dimethylthiourea.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Ghosh, Anindya published the artcileFabrication of a hollow sphere N,S co-doped bifunctional carbon catalyst for sustainable fixation of CO₂ to cyclic carbonates, HPLC of Formula: 191-07-1, the publication is Green Chemistry (2022), 24(4), 1673-1692, database is CAplus.

Execution of compositional doping by more than one element simultaneously inside a carbon matrix is a challenging task for designing advanced carbon-based materials and nanotechnol. Herein, we have integrated a template-free methodol. for the preparation of a hollow sphere N,S co-doped carbon material utilizing melamine and p-toluenesulfonic acid as a nitrogen and sulfur precursor, highlighting a cost-effective, simple, and green process. This N,S dual doped carbon material acted as a promising bifunctional catalyst for sustainable CO₂ fixation to form a cyclic carbonate with an epoxide, and this strategy is appealing for the conversion of CO₂ to chems. The as-synthesized catalyst was comprehensively characterized by FESEM and HRTEM techniques, showing that the formed nanosheets arranged randomly in the shape of a sphere and turned out to be a hollow sphere after carbonization. The XPS anal. revealed that the randomly arranged nanosheets are linked via -C-S-S-C- linkages. The abundance of weakly acidic and basic sites helps to achieve very high activity (GC conversion 95% and selectivity 98%) in a CO₂-epichlorohydrin cycloaddition reaction at 343 K temperature in the presence of a co-catalyst. The exptl. results coupled with the theor. adsorption energy calculation led us to propose that majorly the CO₂ mol. gets adsorbed on the pyridinic N species while epichlorohydrin prefers a terminal -SO₂H acidic site for adsorption. Addnl., the DFT study elucidated the detailed reaction mechanism for the CO₂-epichlorohydrin reaction and identified the attack of CO₂ by the iodoalkoxy anion as the rate-determining step. Beneficially, this study establishes a definitive relationship between CO₂ utilization and an advanced heteroatom doped carbon-based catalyst.

Green Chemistry published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C24H12, HPLC of Formula: 191-07-1.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Ariyo Olusegun, Moses published the artcileUnderstanding the role of flexible alkyl-¦Á,¦Ø-diamine linkers on the substitution behavior of dinuclear trans-platinum(II) complexes: A kinetic and mechanistic study, Formula: C3H8N2S, the publication is Inorganica Chimica Acta (2021), 120420, database is CAplus.

An investigation of the role of flexible alkyl-¦Á,¦Ø-diamine linkers on the substitution behavior of dinuclear trans-platinum(II) complexes. The substitution reactions of four dinuclear trans-platinum(II) complexes viz. [[PtNH₃Cl₂]₂-¦Ì-NH₂(CH₂)₂NH₂] (P12), [[PtNH₃Cl₂]₂-¦Ì-NH₂(CH₂)₃NH₂] (P13), [[PtNH₃Cl₂]₂-¦Ì-NH₂(CH₂)₄NH₂] (P14) and [[PtNH₃Cl₂]₂-¦Ì-NH₂(CH₂)₅NH₂] (P15) with three neutral thiourea-based nucleophiles specifically: thiourea (TU), N-methyl-2-thiourea (MTU) and N,N-dimethyl-2-thiourea (DMTU) were studied quant. under pseudo-first-order condition as function of concentration and temperature by conventional UV-Visible and stopped-flow spectrophotometers. The ligand substitution reaction of the complexes proceeds in veritably three consecutive steps. Each step follows first-order kinetics with the resp. complex and nucleophile. The pseudo first order rate constants, ko_bs(₁/₂/₃), for sequential substitution of the chlorido ligands, the ammine, and subsequent displacement of the linker obeyed the rate law: ko_bs(₁/₂/₃) = k(₁/₂/₃)[NU]. The ligand substitution reactions were driven by both electronic and steric factors. However, our findings revealed that upon the substitution of the chlorido ligands by the nucleophiles at the platinum centers, the ¦Ò-donor capacity via inductive effect of these electron-rich nucleophiles over compensate the steric strain imposed by the nucleophiles and by the alkanediamine linker at the substitution sites. Consequently, electronic factors governed the overall reaction pattern of these complexes. ¹⁹⁵Pt NMR results confirmed the simultaneous substitution of all the chlorido ligands by thiourea-based nucleophiles, followed by the subsequent but successive displacement of the ammine groups and the flexible alkanediamine linker from the metal centers. The order of reactivity of the nucleophiles with the complexes decreases with the increase in steric bulk in the nucleophiles: TU > MTU > DMTU. The small pos. enthalpy and the large but neg. entropy confirm the associative mode of activation for all the studied complexes. Computational modeling using d. functional theory (DFT) calculations was employed to rationalize the kinetic trends.

Inorganica Chimica Acta published new progress about 6972-05-0. 6972-05-0 belongs to catalysis-chemistry, auxiliary class Thiourea,Amine,Aliphatic hydrocarbon chain,Amide, name is 1,1-Dimethylthiourea, and the molecular formula is C3H8N2S, Formula: C3H8N2S.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Mishra, Vivek Kumar published the artcileC-H-Activation approach towards the core structure of the alkaloid ¦Ã-lycorane, SDS of cas: 1293990-73-4, the publication is Tetrahedron (2016), 72(41), 6499-6509, database is CAplus.

With a view towards the synthesis of lycorane-like structures several N-(pivaloyloxy)benzamides were reacted with cyclohexa-1,3-diene in presence of a rhodium(III) catalyst which resulted via C-H activation in the corresponding tetrahydrophenanthridinones, e.g., I. Subsequently, various strategies were explored to convert these tricyclic phenanthridinones to the tetracyclic core structure of the lycoranes. While radical based approaches were not successful, we were able to form ring D (pyrrolidine ring) by a nickel catalyzed reaction, resulting in alkaloid derivatives II [R = CN and H].

Tetrahedron published new progress about 1293990-73-4. 1293990-73-4 belongs to catalysis-chemistry, auxiliary class Aliphatic Chain, name is O-Pivaloylhydroxylamine trifluoromethanesulfonate, and the molecular formula is C6H12F3NO5S, SDS of cas: 1293990-73-4.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Jorea, Alexandra published the artcilePhotocatalyzed Functionalization of Alkenoic Acids in 3D-Printed Reactors, Safety of 3-Benzoylpropionicacid, the publication is ChemSusChem, database is CAplus and MEDLINE.

The valorization of alkenoic acids possibly deriving from biomass (fumaric and citraconic acids) was carried out through conversion in important building blocks, such as ¦Ã-keto acids and succinic acid derivatives The functionalization was carried out by addition onto the C=C double bond of radicals generated under photocatalyzed conditions from suitable hydrogen donors (mainly aldehydes) and by adopting a decatungstate salt as the photocatalyst. Syntheses were performed under batch (in a glass vessel) and flow (by using 3D-printed reactors) conditions. The design of the latter reactors allowed for an improved yield and productivity.

ChemSusChem published new progress about 2051-95-8. 2051-95-8 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene,Ketone, name is 3-Benzoylpropionicacid, and the molecular formula is C10H10O3, Safety of 3-Benzoylpropionicacid.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Park, Sei-Kyoung published the artcileInhibition of A¦Â42 oligomerization in yeast by a PICALM ortholog and certain FDA approved drugs, Application of N1,N2-Dibenzylethane-1,2-diamine, the publication is Microbial Cell (2016), 3(2), 53-64, database is CAplus and MEDLINE.

The formation of small A¦Â42 oligomers has been implicated as a toxic species in Alzheimer disease (AD). In strong support of this hypothesis we found that overexpression of Yap1802, the yeast ortholog of the human AD risk factor, phosphatidylinositol binding clathrin assembly protein (PICALM), reduced oligomerization of A¦Â42 fused to a reporter in yeast. Thus we used the A¦Â42-reporter system to identify drugs that could be developed into therapies that prevent or arrest AD. From a screen of 1,200 FDA approved drugs and drug-like small compounds we identified 7 drugs that reduce A¦Â42 oligomerization in yeast: 3 antipsychotics (bromperidol, haloperidol and azaperone), 2 anesthetics (pramoxine HCl and dyclonine HCl), tamoxifen citrate, and minocycline HCl. Also, all 7 drugs caused A¦Â42 to be less toxic to PC12 cells and to relieve toxicity of another yeast AD model in which A¦Â42 aggregates targeted to the secretory pathway are toxic. Our results identify drugs that inhibit A¦Â42 oligomers from forming in yeast. It remains to be determined if these drugs inhibit A¦Â42 oligomerization in mammals and could be developed as a therapeutic treatment for AD.

Microbial Cell published new progress about 140-28-3. 140-28-3 belongs to catalysis-chemistry, auxiliary class Benzenes, name is N1,N2-Dibenzylethane-1,2-diamine, and the molecular formula is C16H20N2, Application of N1,N2-Dibenzylethane-1,2-diamine.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Namera, Dipti L. published the artcileMicrowave assisted synthesis of 2,5-distyryl-1,3,4-oxadiazole derivatives as antimicrobial agents, Application In Synthesis of 16909-09-4, the publication is International Letters of Chemistry, Physics and Astronomy (2014), 46-54, 9 pp., database is CAplus.

A new series of 2,5-distyryl-1,3,4-oxadiazoles derivatives have been synthesized from cinnamic hydrazide on reaction with various cinnamic acid derivatives The structures of synthesized compounds have been elucidated by spectral studies like IR, 1HNMR, Mass and also Elemental Anal. Furthermore, all synthesized compounds were screened for in vitro anti microbial activity against the gram pos. (Staphylococcus aureus, Pseudomonas aeruginosa) and gram neg. (Escherichia coli) bacterial strain. In which some the compounds show potential inhibition against the test organisms.

International Letters of Chemistry, Physics and Astronomy published new progress about 16909-09-4. 16909-09-4 belongs to catalysis-chemistry, auxiliary class Alkenyl,Carboxylic acid,Benzene,Ether, name is (E)-3-(2,4-Dimethoxyphenyl)acrylic acid, and the molecular formula is C11H12O4, Application In Synthesis of 16909-09-4.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia