Author: Jessica.F

Kodama, Yuki published the artcileStereoselective synthesis of highly functionalized (Z)-chloroalkene dipeptide isostere containing an α,α-disubstituted amino acid, Safety of (S)-2-Methylpropane-2-sulfinamide, the main research area is chloroalkene dipeptide isostere enantioselective diastereoselective synthesis disubstituted amino acid; ketimine Aza Darzens condensation dichloroenolate aldimine; cyclization mechanism transition state free energy NBO DFT; quaternary carbon center spirocyclic crystal mol structure packing.

Described here is the first stereoselective synthesis of highly functionalized chloroalkene dipeptide isosteres containing an α,α-disubstituted amino acid (ααAA). This synthesis requires the construction of a quaternary carbon center, and this challenge was overcome by the Aza-Darzens condensation of ketimine with α,α-dichloroenolate, producing 2-chloroaziridines with quaternary carbon centers including spirocyclic motifs, which are valuable for the previously elusive synthesis of various α,α-AA-containing chloroalkene isosteres.

Chemical Communications (Cambridge, United Kingdom) published new progress about Amino acids Role: PRP (Properties), RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation) (disubstituted). 343338-28-3 belongs to class amides-buliding-blocks, name is (S)-2-Methylpropane-2-sulfinamide, and the molecular formula is C4H11NOS, Safety of (S)-2-Methylpropane-2-sulfinamide.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Kharaneko, A. O. published the artcileSynthesis and Modification of Hetero-Fused Pyrazoles Derived from Methyl 1-(2-Oxo-2-phenylethyl)-3-phenyl-1H-pyrazole-5-carboxylate, Application In Synthesis of 123-39-7, the main research area is hetero fused pyrazole preparation.

A modified procedure has been proposed for the synthesis of 2,7-diphenyl-5,8-dihydro-4H-pyrazolo[5,1-d][1,2,5]triazepin-4-one, and the possibility of transformation of the latter to the pyrazolo[1,5-a]pyrazine system has been demonstrated. Functionalization of 2,7-diphenyl-5,8-dihydro-4H-pyrazolo[5,1-d][1,2,5]triazepin-4-one at the 4-position and fusion of a tetrazole or triazole ring at the C4-N5 bond have been performed.

Russian Journal of Organic Chemistry published new progress about Heterocyclization. 123-39-7 belongs to class amides-buliding-blocks, name is N-Methylformamide, and the molecular formula is C2H5NO, Application In Synthesis of 123-39-7.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Reis Conceicao, Nuno published the artcileKnoevenagel condensation reaction in supercritical carbon dioxide medium using a Zn(II) coordination polymer as catalyst, Product Details of C2H5NO, the main research area is zinc coordination polymer catalyst preparation benzaldehyde Knoevenagel condensation reaction.

The replacement of conventional organic solvents by the so-called “”green solvents”” is a usual approach to more sustainable chem. processes. Supercritical carbon dioxide (scCO2) has been successfully regarded as a candidate for such a purpose. Moreover, it possesses moderate critical pressure and temperature conditions and may be easily separated from the catalytic system by a simple depressurization. In the present work, the new Zn(II) coordination polymer [Zn(L1)(NMeF)]n·n(NMeF) (Zn-CP 1) is reported, being prepared by the solvothermal reaction of 5-{(pyren-4-ylmethyl)amino}isophthalic acid (H2L1) with Zn(NO3)2·6H2O in N-methylformamide (NMeF). The SCXRD anal. revealed that Zn-CP 1 has a 1D double chain type of structure. Its potential as catalyst was studied in the Knoevenagel condensation of benzaldehyde and malononitrile as a model reaction under mild conditions, in scCO2 medium. An increasing trend was observed in the reaction yield as we moved from aprotic (THF) to protic (EtOH and H2O) polar co-solvents, reaching the full conversion in the case of water. It was found that scCO2, in the absence of a protic co-solvent, is not the most suitable medium for this reaction. The catalyst can be recycled without a considerable loss of activity; SEM, PXRD, FT-IR and TGA analyzes indicate its high stability throughout the process.

Inorganica Chimica Acta published new progress about Crystal structure. 123-39-7 belongs to class amides-buliding-blocks, name is N-Methylformamide, and the molecular formula is C2H5NO, Product Details of C2H5NO.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Zhang, Minxuan published the artcileK3PO4-Promoted domino reactions: diastereoselective synthesis of trans-2,3-dihydrobenzofurans from salicyl N-tert-butanesulfinyl imines and sulfur ylides, Product Details of C4H11NOS, the main research area is trans dihydrobenzofuran preparation chemoselective enantioselective diastereoselective; salicyl tert butylsulfinyl imine preparation sulfur ylide domino annulation.

An efficient domino annulation between sulfur ylides and salicyl N-tert-butylsulfinyl imines was developed. The reaction proceeded with a diastereodivergent process, the configuration of the sulfinyl group determining the stereochem. course of the reaction. The method allowed the synthesis of a highly substituted trans-2,3-dihydrobenzofuran skeletons I [R1 = H, 4-Cl, 4-Me, 4-NO2; R2 = H; R3 = H, Cl, Br; R4 = H, Cl; R2R3 = CH:CC:CH] with high yield and good chemo- and diastereoselectivity.

RSC Advances published new progress about Chemoselectivity. 343338-28-3 belongs to class amides-buliding-blocks, name is (S)-2-Methylpropane-2-sulfinamide, and the molecular formula is C4H11NOS, Product Details of C4H11NOS.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Xu, Ze-Ming published the artcileExogenous Photosensitizer-, Metal-, and Base-Free Visible-Light-Promoted C-H Thiolation via Reverse Hydrogen Atom Transfer, Safety of 4-Methoxy-N-phenylbenzamide, the main research area is benzothiazole preparation; photochem oxidative cyclization arylthioamide TEMPO catalyst; oxidative photochem intramol thiolation arylthioamide TEMPO catalyst; mechanism kinetics kinetic isotope effect photochem oxidative cyclization arylthioamide; reduction oxidation potential arylthioamide TEMPO.

N-Arylthioamides such as N-phenylthiobenzamide underwent photochem. visible-light oxidative cyclization reactions in the presence of TEMPO to yield benzothiazoles such as 2-phenylbenzothiazole without added photosensitizer, metal catalyst, or base. The mechanism of the reaction was studied by evaluation of the oxidation and reduction potentials of TEMPO and of selected reactants, determination of the kinetics of and kinetic isotope effects on the reaction, and mass spectrometric identification of reaction intermediates. The reaction likely occurs by absorption of visible light by thioamides to generate their excited states which undergo reverse hydrogen-atom transfer (RHAT) with 2,2,6,6-tetramethylpiperidine N-oxyl to form sulfur radicals; cyclization of the sulfur radicals onto the aryl ring followed by rearomatization via RHAT yields the benzothiazole products.

Organic Letters published new progress about Isotope effect. 7465-88-5 belongs to class amides-buliding-blocks, name is 4-Methoxy-N-phenylbenzamide, and the molecular formula is C14H13NO2, Safety of 4-Methoxy-N-phenylbenzamide.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Zhang, Stephanie J. published the artcilePotentially Prebiotic Activation Chemistry Compatible with Nonenzymatic RNA Copying, SDS of cas: 123-39-7, the main research area is nonenzymic RNA replication life origin primer extension.

The nonenzymic replication of RNA may have enabled the propagation of genetic information during the origin of life. RNA copying can be initiated in the laboratory with chem. activated nucleotides, but continued copying requires a source of chem. energy for in situ nucleotide activation. Recent work has illuminated a potentially prebiotic cyanosulfidic chem. that activates nucleotides, but its application to nonenzymic RNA copying had not been demonstrated. Here, we report a novel pathway that activates RNA nucleotides in a manner compatible with template-directed nonenzymic copying. We show that this pathway, which we refer to as bridge-forming activation, selectively yields the reactive imidazolium-bridged dinucleotide intermediate required for copying. Our results will enable more realistic simulations of RNA propagation based on continuous in situ nucleotide activation.

Journal of the American Chemical Society published new progress about Life, origin. 123-39-7 belongs to class amides-buliding-blocks, name is N-Methylformamide, and the molecular formula is C2H5NO, SDS of cas: 123-39-7.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Ma, Xin published the artcileProtonated Ground-State Singlet meta-Pyridynes React from an Excited Triplet State, Quality Control of 123-39-7, the main research area is protonated meta pyridyne singlet ground triplet excited state reactivity.

The gaseous 2,6-didehydropyridinium cation and its derivatives transfer a proton to reagents for which the reaction for their singlet ground states is too endothermic to be observed These reactions occur from the lowest-energy excited triplet states, which has not been observed (or reported) for other meta-benzyne analogs. Quantum chem. calculations indicate that the (excited) triplet states are stronger Bronsted acids than their (ground) singlet states, likely due to unfavorable three-center, four-electron interactions in the singlet-state conjugate bases. The cations have substantially smaller (calculated) singlet-triplet (S-T) splittings (ranging from ca. -11 to -17 kcal mol-1) than other related meta-benzyne analogs (e.g., -23.4 kcal mol-1 for the 3,5-isomer). This is rationalized by the destabilization of the singlet states (relative to the triplet states) by reduced (spatial) overlap of the nonbonding MOs due to the presence of the nitrogen atom between the radical sites (making the ring more rigid). Both the singlet and triplet states are believed to be generated upon formation of these biradicals via energetic collisions due to their small S-T splittings. It appears that once the triplet states are formed, the rate of proton transfer is faster than the rate of intersystem crossing unless the biradicals contain heavy atoms.

Journal of Organic Chemistry published new progress about Crystal structure. 123-39-7 belongs to class amides-buliding-blocks, name is N-Methylformamide, and the molecular formula is C2H5NO, Quality Control of 123-39-7.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Das, Pradipta published the artcileDramatic Effect of γ-Heteroatom Dienolate Substituents on Counterion Assisted Asymmetric Anionic Amino-Cope Reaction Cascades, Related Products of amides-buliding-blocks, the main research area is counterion assisted anionic cascade Mannich reaction Cope rearrangement cyclization.

We report a dramatic effect on product outcomes of the lithium ion enabled amino-Cope-like anionic asym. cascade when different γ-dienolate heteroatom substituents are employed. For dienolates with azide, thiomethyl, and trifluoromethylthiol substituents, a Mannich/amino-Cope/cyclization cascade ensues to form chiral cyclohexenone products with two new stereocenters in an anti-relationship. For fluoride-substituted nucleophiles, a Mannich/amino-Cope cascade proceeds to afford chiral acyclic products with two new stereocenters in a syn-relationship. Bromide- and chloride-substituted nucleophiles appear to proceed via the same pathway as the fluoride albeit with the added twist of a 3-exo-trig cyclization to yield chiral cyclopropane products with three stereocenters. When this same class of nucleophiles is substituted with a γ-nitro group, the Mannich-initiated cascade is now diverted to a β-lactam product instead of the amino-Cope pathway. These anionic asym. cascades are solvent- and counterion-dependent, with a lithium counterion being essential in combination with ethereal solvents such as MTBE and CPME. By altering the geometry of the imine double bond from E to Z, the configurations at the R1 and X stereocenters are flipped. Mechanistic, computational, substituent, and counterion studies suggest that these cascades proceed via a common Mannich-product intermediate, which then proceeds via either a chair (X = N3, SMe, or SCF3) or boat-like (X = F, Cl, or Br) transition state to afford amino-Cope-like products or β-lactam in the case of X = NO2.

Journal of the American Chemical Society published new progress about Chiral auxiliary. 343338-28-3 belongs to class amides-buliding-blocks, name is (S)-2-Methylpropane-2-sulfinamide, and the molecular formula is C4H11NOS, Related Products of amides-buliding-blocks.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Yoshinaga, Yukako published the artcileStereoinvertive C-C Bond Formation at the Boron-Bound Stereogenic Centers through Copper-Bipyridine-Catalyzed Intramolecular Coupling of α-Aminobenzylboronic Esters, Application of (S)-2-Methylpropane-2-sulfinamide, the main research area is bromobenzamidobenzylic boronate nonracemic preparation; isoindolinone nonracemic preparation; copper bipyridine catalyst intramol Suzuki coupling bromobenzamidobenzylic boronate inversion; bipyridine ligand; carbon stereocenters; copper; enantiospecificity; stereospecific reaction.

Nonracemic α-(bromobenzamido)benzylic boronates such as I (R = Me, n-Pr, PhCH2CH2) and ent-I (R = H) underwent stereospecific intramol. Suzuki coupling reactions in the presence of CuCl2 and 2,2′-bipyridine or 6-phenyl-2,2′-bipyridine and mediated by Cs2CO3 and H2O (and in some cases phenol) in toluene/chloroform to yield nonracemic isoindolinones such as II (R = Me, n-Pr, PhCH2CH2) and ent-II (R = H) with inversion of boronate stereochem.

Angewandte Chemie, International Edition published new progress about Cyclization catalysts, stereoselective. 343338-28-3 belongs to class amides-buliding-blocks, name is (S)-2-Methylpropane-2-sulfinamide, and the molecular formula is C4H11NOS, Application of (S)-2-Methylpropane-2-sulfinamide.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics