Catalysis-chemistry

Bateman, L. published the artcileTautomeric equilibria in 1,3(4),8-triene-type olefins. An investigation of double-bond interaction through two methylene groups, Recommanded Product: 2-Methyl-4-phenylbutanoic acid, the publication is Journal of the Chemical Society (1951), 2290-8, database is CAplus.

cf. preceding abstract Recent evidence and theories concerned with the bond contraction of the CH₂CH₂ moiety in 1,5-dienes (cf. Szwarc, C.A. 43, 5306e) are summarized. The tautomeric systems PhCH₂CH:CMe(CH₂)₂Ph (I) ? PhCH:CHCHMe(CH₂)₂Ph (II) and PhCH₂CH:CMe(CH₂)₂CH:CMe₂ (III) ? PhCH:CHCHMe(CH₂)₂CH:CMe₂ (IV) are investigated by the method described in the preceding abstract In both cases the equilibrium mixtures contain 36% non-conjugated isomer, I and III, resp., which is in excellent agreement with the value of 35% predicted with the assumption that the 1,5-diene unit is without special effect. [Ph(CH₂)₂]₂C(OH)Me (from (PhCH₂CH₂)₂CO and MeMgI) heated with 30% aqueous H₂SO₄ gave I, b_0.5 126¡ã, n_D¹⁴ 1.5605, containing about 7% Ph(CH₂CH₂)₂C:CH₂.Ph(CH₂)₂CH(OH)Me treated with PBr₃ at -10¡ã and then heated at 100¡ã gave Ph(CH₂)₂CHBrMe (V), b₁₄ 116-18¡ã, n_D²² 1.5351. Ph(CH₂)₂CHMeMgBr from 76 g. V and 9 g. Mg in 250 cc. Et₂O was added rapidly to 300 g. solid, powd. CO₂, and the mixture decomposed with ice and HCl to yield 25 g. Ph(CH₂)₂CHMeCO₂H (VI), b_0.006 105-7¡ã, n_D²⁰ 1.5113. VI and LiAlH₄ in Et₂O gave almost quant. Ph(CH₂)₂CHMeCH₂OH, b₁₁ 135¡ã, n_D¹⁶ 1.5173, which was converted with PBr₃ to Ph(CH₂)₂CHMeCH₂Br (VII), b₁₄ 129¡ã, n_D¹⁸ 1.5344. The Grignard derivative from 22.7 g. VII and 10.7 g. BzH in Et₂O gave 17 g. PhCH(OH)CH₂CHMe(CH₂)₂Ph (VIII), b_0.01 135-6¡ã, n_D¹⁶ 1.5506. VIII (3.8 g.) heated 1 h. with 1.9 g. NaHSO₄ at 160¡ã gave 2 g. II b_0.01 110¡ã, n_D¹⁸ 1.5710. Ph(CH₂)₂CHMeMgBr from 76 g. V and 42 g. PhCH₂CHO in Et₂O gave 28 g. PhCH₂CH(OH)CHMe(CH₂)₂Ph, b_0.005 132-4¡ã, n_D¹⁸ 1.5565, which was dehydrated with NaHSO₄ as above to give a mixture, b_0.006 98-100¡ã, of 74% I and 26% II. PhCH(OH)CH₂CHMe(CH₂)₂CH:CMe₂, b_0.01 100-2¡ã, n_D¹⁶ 1.5132 (from citronellal and PhMgBr), was dehydrated with NaHSO₄ at 160¡ã for 1 h. under N to give IV, b_0.01 80¡ã, n_D²⁰ 1.5287. MeCH(OH)(CH₂)₂CH:CMe₂, b₁₀ 73¡ã, n_D¹⁸ 1.4498, (from Ac(CH₂)₂CH:CMe₂ and LiAlH₄) and PBr₂ gave MeCHBr(CH₂)₂CH:CMe₂ (IX), b₁₂ 60¡ã, n_D¹⁹ 1.4711. The Grignard derivative of IX and PhCH₂CHO gave PhCH₂CH(OH)CHMe(CH₂)₂CH:CMe₂ (X), b_0.006 97-8¡ã, n_D¹⁷ 1.5155. X heated with B(OH)₃ gave an ester which decomposed at 340¡ã to give a mixture, b_0.01 75¡ã, of 75% III and 25% IV. The Grignard derivative of citronellyl bromide and BzH gave PhCH(OH)(CH₂)₂CHMe(CH₂)₂CH:CMe₂, b_0.01 110¡ã, n_D¹⁵ 1.5085, which was readily dehydrated with NaHSO₄ at 160¡ã to PhCH:CHCH₂CHMe(CH₂)₂CH:CMe₂ (XI), b_0.01 89-90¡ã, n_D¹⁶ 1.5250. The isomerization of XI gave an equilibrium mixture containing 9.5% PhCH₂CH:CHCHMe(CH₂)₂CH:CMe₂.

Journal of the Chemical Society published new progress about 1949-41-3. 1949-41-3 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene, name is 2-Methyl-4-phenylbutanoic acid, and the molecular formula is C11H14O2, Recommanded Product: 2-Methyl-4-phenylbutanoic acid.

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

Zhu, Jing published the artcileRadical Hydrosilylation of Alkynes Catalyzed by Eosin Y and Thiol under Visible Light Irradiation, Related Products of catalysis-chemistry, the publication is Organic Letters (2018), 20(11), 3174-3178, database is CAplus and MEDLINE.

A visible light-promoted hydrosilylation of alkynes was explored and achieved using 1 mol % organic dye Eosin Y as the photocatalyst and a catalytic amount of thiol as the radical quencher. The corresponding alkenylsilanes were provided with high regio- and stereoselectivites in the reactions of various terminal and internal alkynes. The reaction is preferentially initiated by a single electron transfer process, and a photoredox pathway is suggested.

Organic Letters published new progress about 22693-41-0. 22693-41-0 belongs to catalysis-chemistry, auxiliary class Other Functionalization Reagent, name is 2,4,6-Triisopropylbenzenethiol, and the molecular formula is C7H5ClN2S, Related Products of catalysis-chemistry.

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

Sun, Lei published the artcileNIS-Mediated Intramolecular sp³ C-H Oxidation of 2-Alkyl-Substituted Benzamides, HPLC of Formula: 118-90-1, the publication is European Journal of Organic Chemistry, database is CAplus.

The N-iodosuccinimide-mediated benzyl sp³ C-H oxidation of 2-alkyl-substituted benzamide derivatives was described. This Hofmann-Loffler-Freytag (HLF) type reaction involving intramol. sp³ C-O bond formation differs from the construction of the C-N bond in the classic and modified HLF reactions. This reaction proceeded smoothly via 1,5-hydrogen atom transfer of N-centered radicals directly afforded by in-situ N-I bond generation, provided iminoisobenzofuran derivatives in moderate to excellent yields with exclusive chemoselectivity.

European Journal of Organic Chemistry published new progress about 118-90-1. 118-90-1 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene,Natural product, name is 2-Methylbenzoic acid, and the molecular formula is C6H5NO, HPLC of Formula: 118-90-1.

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

Gonzalez-Nogal, Ana M. published the artcileSome synthetic applications of vinylphosphane oxides, Application In Synthesis of 4141-48-4, the publication is Tetrahedron (2010), 66(50), 9610-9619, database is CAplus.

Vinylphosphine oxides have been used as Michael acceptors for the diastereoselective synthesis of anti ¦Á-functionalized-¦Â-silylated phosphine oxides and ¦Â-stannyl-, ¦Â-phenylthio- or ¦Â-phosphinyl phosphine oxides. Although the utility of these substrates as dipolarophiles was more limited, authors have obtained a mixture of 3- and 4-phosphinylpyrazoles in which the latter is the major regioisomer, by 1,3-cycloaddition with N-phenylsydnone. Moreover, vinylphosphine oxides reacted with aldehydes in the presence of LDA by a Baylis-Hillman type reaction, leading to (E)-¦Â-hydroxyphosphine oxides, which were readily converted in allenes. It is noteworthy that the application of this methodol. to silylated substrates has permitted us to synthesize an interesting and more versatile silylallene.

Tetrahedron published new progress about 4141-48-4. 4141-48-4 belongs to catalysis-chemistry, auxiliary class Aryl phosphine ligand,Mono-phosphine Ligands, name is Allyldiphenylphosphine oxide, and the molecular formula is C15H15OP, Application In Synthesis of 4141-48-4.

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

Gonzalez-Nogal, Ana M. published the artcileEpoxysilanes as substrates in regio- and stereo-specific synthesis of silylated ¦Ã-hydroxyphosphane oxides, precursors of stereodefined allylphosphane oxides, Product Details of C15H15OP, the publication is Tetrahedron (2013), 69(37), 8080-8087, database is CAplus.

Epoxysilanes experienced trans stereospecific ¦Á- or ¦Â-cleavage by the Li derivative of methyldiphenylphosphine oxide leading to different compounds The behavior of the epoxysilanes towards this nucleophilic reagent depends on the nature of the silyl group, the position of the substituents and the configuration of the epoxysilane. Unsubstituted and cis ¦Â-substituted dimethylphenylsilylepoxides underwent ¦Á-nucleophilic attack of Li methyldiphenylphosphine oxide giving stereodefined ¦Ã-phosphino-¦Â-silylalcs. Nevertheless, in the same conditions the intermediate ¦Â-hydroxysilane, formed by ¦Á-opening from trans ¦Â-substituted dimethylphenylsilylepoxides, experienced Peterson elimination to give stereodefined allylphosphine oxides. The steric requirements for the nucleophilic attack determined the regiochem. of the reaction. ¦Á-Substituted phenyldimethylsilyl- and tert-butyldiphenylsilylepoxides were exclusively attacked at the ¦Â-position affording ¦Ã-hydroxy-¦Ã-silylphosphine oxides and ¦Ã-phosphino silyl ether, resulting from Brook rearrangement. However, the allylphosphine oxides resulting from syn- or anti-elimination of ¦Â-dimethylphenylsilyl-¦Ã-hydroxyphosphine oxides, are of interest in the synthesis of phosphorylated and functionalized building blocks.

Tetrahedron published new progress about 4141-48-4. 4141-48-4 belongs to catalysis-chemistry, auxiliary class Aryl phosphine ligand,Mono-phosphine Ligands, name is Allyldiphenylphosphine oxide, and the molecular formula is C15H15OP, Product Details of C15H15OP.

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

Cavalla, David published the artcileHorner-Wittig reactions of ¦Â-aminoalkyl- and [¦Â-(acylamino)alkyl]diphenylphosphine oxides: synthesis of N-allylamines and -amides and 5-(diphenylphosphinoyl)-2-phenyl-5,6-dihydro-4H-1,3-oxazines, Formula: C15H15OP, the publication is Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999) (1987), 1883-98, database is CAplus.

Lithium derivatives of [(¦Â-diphenylphosphinoyl)alkyl]amines and dilithium derivatives of the corresponding amides combine with aldehydes or ketones in the Horner-Wittig reaction. Separation of the diastereoisomeric intermediates leads to single positional and geometric isomers of N-allylamines and amides. Thus, treatment of Ph₂P(O)CH₂CH₂NR₂ [R₂ = (CH₂)₅, CH₂CH₂OCH₂CH₂] with BuLi, followed by Me₂CO, afforded erythro– and threo-Ph₂P(O)CH[CMe₂(OH)]CH₂NR₂, which were separated by fractional crystallization, then treated with NaH in DMF to give elimination products Z– and E-MeCH:CHCH₂NR, resp. Attempted rearrangement of the same intermediates in acid solution gave dihydrooxazines or, in one case, a [¦Ã-(acylamino)allyl]diphenylphosphine oxide. The x-ray crystal structure of syn,anti-[(acylamino)hydroxypentyl]diphenylphosphine oxide I was determined

Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999) published new progress about 4141-48-4. 4141-48-4 belongs to catalysis-chemistry, auxiliary class Aryl phosphine ligand,Mono-phosphine Ligands, name is Allyldiphenylphosphine oxide, and the molecular formula is C15H15OP, Formula: C15H15OP.

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

Wargny, Matthieu published the artcileNutritional biomarkers and heart failure requiring hospitalization in patients with type 2 diabetes: the SURDIAGENE cohort, Related Products of catalysis-chemistry, the publication is Cardiovascular Diabetology (2022), 21(1), 101, database is CAplus and MEDLINE.

Heart failure (HF) is a growing complication and one of the leading causes of mortality in people living with type 2 diabetes (T2D). Among the possible causes, the excess of red meat and the insufficiency of vegetables consumption are suspected. Such an alimentation is associated with nutritional biomarkers, including trimethylamine N-oxide (TMAO) and its precursors. Here, we aimed to study these biomarkers as potential prognostic factors for HF in patients with T2D. We used the SURDIAGENE (SURvival DIAbetes and GENEtics) study, a large, prospective, monocentric cohort study including 1468 patients with T2D between 2001 and 2012. TMAO and its precursors (trimethylamine [TMA], betaine, choline, and carnitine) as well as thio-amino-acids (cysteine, homocysteine and methionine) were measured by liquid chromatog.-tandem mass spectrometry. The main outcome was HF requiring Hospitalization (HFrH) defined as the first occurrence of acute HF leading to hospitalization and/or death, established by an adjudication committee, based on hospital records until 31st Dec. 2015. The secondary outcomes were the composite event HFrH and/or cardiovascular death and all-cause death. The association between the biomarkers and the outcomes was studied using cause-specific hazard-models, adjusted for age, sex, history of coronary artery disease, NT-proBNP, CKD-EPI-derived eGFR and the urine albumin/creatinine ratio. Hazard-ratios (HR) are expressed for one standard deviation. The data of interest were available for 1349/1468 of SURDIAGENE participants (91.9%), including 569 (42.2%) women, with a mean age of 64.3 ¡À 10.7 years and a median follow-up of 7.3 years [25th-75th percentile, 4.7-10.8]. HFrH was reported in 209 patients (15.5%), HFrH and/or cardiovascular death in 341 (25.3%) and all-cause death in 447 (33.1%). In unadjusted hazard-models, carnitine (HR = 1.20, 95% CI [1.05; 1.37]), betaine (HR = 1.34, [1.20; 1.50]), choline (HR = 1.35, [1.20; 1.52]), TMAO (HR = 1.32, [1.16; 1.50]), cysteine (HR = 1.38, [1.21; 1.58]) and homocysteine (HR = 1.28, [1.17; 1.39]) were associated with HFrH, but not TMA and methionine. In the fully adjusted models, none of these associations was significant, neither for HFrH nor for HFrH and/or CV death, when homocysteine only was pos. associated with all-cause death (HR = 1.16, [1.06; 1.27]). TMAO and its precursors do not appear to be substantial prognosis factors for HFrH, beyond usual cardiac- and kidney-related risk factors, whereas homocysteine is an independent risk factor for all-cause death in patients with T2D.

Cardiovascular Diabetology published new progress about 63-68-3. 63-68-3 belongs to catalysis-chemistry, auxiliary class Natural product, name is (S)-2-Amino-4-(methylthio)butanoic acid, and the molecular formula is C6H8O3, Related Products of catalysis-chemistry.

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

Trujillo, Cristina published the artcileMechanistic Insights into the Organocatalytic Kinetic Resolution of Oxazinones through Alcoholysis, Product Details of C10H10O3, the publication is European Journal of Organic Chemistry (2022), 2022(3), e202100818, database is CAplus.

A complete computational study has been performed in order to rationalise the results of a new organocatalytic approach to the kinetic resolution of 4-substituted oxazinones which results in highly enantioenriched and orthogonally-protected ¦Â-amino acids. DFT-anal. elucidated the preferable binding orientation of the 4-oxazinone under study, predicted the formation of the observed major R product with a calculated ee in good agreement with the exptl. data and allowed a complete mechanistic and stereochem. understanding of the catalysis. The alcoholytic kinetic resolution of a 7-memebered ring analog to generate enantioenriched ¦Ã-amino acids was exptl. and computationally investigated for the first time.

European Journal of Organic Chemistry 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 C6H12N2O, Product Details of C10H10O3.

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

Beswick, Michael A. published the artcileMetal selection of ligand functionality in [(mes)₂PO₂Li¡¤2thf]₂ and [{(Me₃Si)₂N}Cd{(mes)₂P-O}₂Li¡¤2thf] (mes = C₆H₂Me₃-2,4,6), Recommanded Product: Dimesitylphosphine oxide, the publication is Chemical Communications (Cambridge) (1997), 583-584, database is CAplus.

The reaction of LiBu with [(mes)₂P(H):O] affords the diorganophosphinate complex [(mes)₂PO₂Li¡¤2THF] (1) and [(mes)₂PLi], however, addition of [Cd{N(SiMe₃)₂}₂] to the mixture gives the diorganophosphinite complex [{(Me₃Si)₂N}Cd{(mes)₂P-O}₂Li¡¤2THF] (2). The formation of these complexes illustrates that the ligand functionality of 1 can be controlled by the character of the coordinated metal ion. 1 And 2 were characterized by x-ray crystallog. (1: triclinic, space group P1?, R₁ = 0.045; 2: monoclinic, space group C2/c, R₁ = 0.064).

Chemical Communications (Cambridge) 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, Recommanded Product: Dimesitylphosphine oxide.

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

Nurchi, Valeria M. published the artcileComplex formation equilibria of Cu^II and Zn^II with triethylenetetramine and its mono- and di-acetyl metabolites, Application In Synthesis of 38260-01-4, the publication is Dalton Transactions (2013), 42(17), 6161-6170, database is CAplus and MEDLINE.

Triethylenetetramine (TETA) dihydrochloride, or trientine, is a therapeutic mol. that has long been used as a copper-chelating agent for the second-line treatment of patients with Wilson’s disease. More recently, it has also been employed as an exptl. therapeutic mol. in diabetes where it improves cardiac structure in patients with diabetic cardiomyopathy and left-ventricular hypertrophy. TETA is metabolized by acetylation, which leads to the formation of two main metabolites in humans and other mammals, monoacetyl-TETA (MAT) and diacetyl-TETA (DAT). These metabolites have been identified in the plasma and urine of healthy and diabetic subjects treated with TETA, and could themselves play a role in TETA-mediated copper chelation and restoration of physiol. copper regulation in diabetes. In this regard, a potentiometric and spectrophotometric study of Cu^II-complex formation equilibrium of TETA, MAT and DAT is presented here, to provide a comprehensive evaluation of the stoichiometries of the complexes formed and of their relative stability constants A potentiometric study has also been conducted on the corresponding Zn^II complexes, to evaluate any possible interference with TETA-mediated Cu^II binding by this second physiol. transition-metal ion, which is present in similar concentrations in human plasma and which also binds to TETA. An ESI-MS study of these systems has both confirmed the complex formation mechanisms established from the potentiometric and spectrophotometric results, and in addition provided direct information on the stoichiometry of the complexes formed in solution These data when taken together show that the 1 : 1 complexes formed with Cu^II and Zn^II have different degrees of protonation. The stability of the Cu^II and Zn^II complexes with the three ligands, evaluated by the parameters pCu and pZn, decreases with the introduction of the acetyl groups. Nevertheless the stability of Cu^II complexes with MAT is sufficiently high to enable its participation in copper scavenging from the patient. A speciation study of the behavior of TETA and MAT with Cu^II in the presence of Zn^II at peri-physiol. plasma concentrations is also presented. While Zn^II did not hinder copper binding, the possibility is raised that prolonged TETA treatment could possibly alter the homeostatic regulation of this essential metal ion. The lack of reliable literature stability constants concerning the Cu^II and Zn^II interaction with the major transport proteins in plasma is also briefly considered.

Dalton Transactions published new progress about 38260-01-4. 38260-01-4 belongs to catalysis-chemistry, auxiliary class Chelating Agents, name is N1,N1′-(Ethane-1,2-diyl)bis(ethane-1,2-diamine) dihydrochloride, and the molecular formula is C6H20Cl2N4, Application In Synthesis of 38260-01-4.

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