Day: November 11, 2022

Brumfield, Martha A. published the artcileTwo triplets mediating intramolecular photochemical abstraction of hydrogen by nitrogen in 4-acyl-6-alkylpyrimidines, Recommanded Product: 1-(6-Methylpyrimidin-4-yl)ethanone, the main research area is photocyclization acylalkylpyrimidine; intramol photochem hydrogen abstraction acylalkylpyrimidine; triplet state hydrogen abstraction acylaklylpyrimidine; pyrimidine acylalkyl triplet photochem.

Direct irradiation with λ >340 nm of 4-acyl-6-alkylpyrimidines I (R = Me) and II (R = CH2CH2CHMe2) or their triplet sensitization by aromatic ketones leads to an nπ* triplet (ET ∼70-71 kcal/mol). In I (R = Me) this state is responsible for hydrogen abstraction from the C(4) side chain and isomerization to cyclopropanol III. Ketone II (R = CH2CH2CHMe2) does not fragment under either of these direct or sensitized conditions. However, triplet sensitization of II (R = CH2CH2CHMe2) by acetone (ET ∼79-82 kcal/mol) or direct irradiation of II (R = CH2CH2CHMe2) through Vycor, λ > 200 nm, leads to hydrogen abstraction, cleavage of the C(6) side chain, and formation of II (R = Me) in a reaction occurring from an upper nπ* triplet (ET ∼79-84 kcal/mol). Ketone I (R = CH2CH2CHMe2) yields mainly IV and, depending upon conditions, a small amount of I (R = Me) or III; the minor products arise by a novel monophotonic pathway.

Journal of the American Chemical Society published new progress about Photoabstraction reaction, intramolecular photoabstraction. 67073-96-5 belongs to class pyrimidines, name is 1-(6-Methylpyrimidin-4-yl)ethanone, and the molecular formula is C7H8N2O, Recommanded Product: 1-(6-Methylpyrimidin-4-yl)ethanone.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Klumpp, Douglas A. published the artcileElectrophilic activation of acetyl-substituted heteroaromatic compounds, Computed Properties of 66373-25-9, the main research area is electrophilic activation condensation benzene heteroaromatic compound; superacid mediated condensation heteroaromatic methyl ketone benzene.

The chem. of acetyl-substituted pyridines, thiazoles, quinoline, isoquinolines, and pyrazine, e.g., thiazole I, has been studied. These heteroarenes condense with benzene in good yields (74-96%) in the Bronsted superacid, CF3SO3H (triflic acid). Thus, reaction of I gave diphenylthiazole II in 91% yield. In these acid-catalyzed hydroxyalkylation reactions, the heteroarene compounds are significantly more reactive than acetophenone. It is proposed that the heteroarene compounds readily form dicationic electrophiles in triflic acid.

Journal of Organic Chemistry published new progress about Aryl ketones Role: RCT (Reactant), RACT (Reactant or Reagent). 66373-25-9 belongs to class pyrimidines, name is 1-(2-Amino-4-methylpyrimidin-5-yl)ethanone, and the molecular formula is C7H9N3O, Computed Properties of 66373-25-9.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Wei, Xiao-Jing published the artcileVisible-Light-Promoted Iron-Catalyzed C(sp2)-C(sp3) Kumada Cross-Coupling in Flow, Formula: C5H5ClN2S, the main research area is Kumada cross coupling aryl chloride Grignard reagent iron catalyst; visible light Kumada cross coupling iron catalyst mechanism flow; Kumada coupling; cross-coupling; flow chemistry; iron catalysis; photocatalysis.

A continuous-flow, visible-light-promoted method has been developed to overcome the limitations of iron-catalyzed Kumada-Corriu cross-coupling reactions. A variety of strongly electron rich aryl chlorides, previously hardly reactive, could be efficiently coupled with aliphatic Grignard reagents at room temperature in high yields and within a few minutes’ residence time, considerably enhancing the applicability of this iron-catalyzed reaction. The robustness of this protocol was demonstrated on a multigram scale, thus providing the potential for future pharmaceutical application. The mechanism was studied using radical clock experiments, kinetic measurements, DFT and other techniques.

Angewandte Chemie, International Edition published new progress about Aryl chlorides Role: RCT (Reactant), RACT (Reactant or Reagent). 38275-42-2 belongs to class pyrimidines, name is 5-Chloro-2-(methylthio)pyrimidine, and the molecular formula is C5H5ClN2S, Formula: C5H5ClN2S.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Li, Yanjun published the artcileOrganophotocatalytic selective deuterodehalogenation of aryl or alkyl chlorides, Application In Synthesis of 439692-55-4, the main research area is deuterated aryl heteroaryl compound green preparation; aryl chloride alkyl organophotocatalyst selective deuterodehalogenation.

A photocatalytic system consisting of an aryl-amine photocatalyst and a disulfide co-catalyst in the presence of sodium formate as an electron and hydrogen donor was developed. Accordingly, many aryl chlorides, alkyl chlorides, and other halides were converted to deuterated products at room temperature in air (>90 examples, up to 99% D-incorporation). The mechanistic studies revealed that the aryl amine served as reducing photoredox catalyst to initiate cleavage of the C-Cl bond, at the same time as energy transfer catalyst to induce homolysis of the disulfide for consequent deuterium transfer process. This economic and environmentally-friendly method could be used for site-selective D-labeling of a number of bioactive mols. and direct H/D exchange of some drug mols.

Nature Communications published new progress about Acid chlorides Role: RCT (Reactant), RACT (Reactant or Reagent). 439692-55-4 belongs to class pyrimidines, name is Thieno[2,3-d]pyrimidine, 4-chloro-6-(1,1-dimethylethyl)-, and the molecular formula is C10H11ClN2S, Application In Synthesis of 439692-55-4.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia