Easy peasy: The title reaction employs N-formylsaccharin, which is an easily accessible crystalline compound, as effective CO source. reactions proceed with a small excess of the source at moderate temperatures and were successfully applied to wide range aryl bromides. DMF=N,N-dimethylformamide, dppb=1,4-bis-(diphenylphosphino)butane.

Catalytic enantioselective alpha-hydrazination of 1,3-dicarbonyl compounds with azodicarboxylates was investigated in the presence our newly developed hydrogen bonding catalyst, squaramide 3j. High yields and high enantioselectivities were achieved low catalyst loading under mild conditions.

Sulfoxides were first introduced to the allylation of N-acylhydrazones with allyltrichlorosilanes as effective neutral coordinate-organocatalysts (NCOs). Both high diastereo- and enantioselectivity attained when optically active chiral sulfoxides used. Asymmetric crotylations using (Z)- (E)-crotyltrichlorosilanes showed a level stereospecificity (Z --> anti E syn) enantioselectivity.

The origin of dolomite is a long-standing enigma in sedimentary geology. It has been proposed that microorganisms, especially anaerobic can overcome kinetic barriers to facilitate precipitation, although their specific role formation still unclear. Our experimental results demonstrate disordered be synthesized at room temperature abiotically from solutions containing polysaccharides such as carboxymethyl cellulose or agar. We propose when dissolved solution, strongly adsorbed on Ca-Mg...

Highly efficient palladium-catalyzed carbonylation of aryl, alkenyl, and allyl halides with phenyl formate is reported. This procedure does not use carbon monoxide affords one-carbon-elongated carboxylic acid esters in excellent yields. The reaction proceeds smoothly under mild conditions tolerates a wide range functional groups including aldehyde, ether, ketone, ester, cyano groups. Furthermore, variety heteroaromatic bromides can be converted to the corresponding high

N-Formylsaccharin, an easily accessible crystalline compound, has been employed as efficient CO source in Pd-catalyzed fluorocarbonylation of aryl halides to afford the corresponding acyl fluorides high yields. The reactions use a near-stoichiometric amount (1.2 equiv) and tolerate diverse functional groups. obtained could be readily transformed into various carboxylic acid derivatives such acid, esters, thioesters, amides one-pot procedure.

The high utility of 2,4,6-trichlorophenyl formate, a highly reactive and easily accessible crystalline CO surrogate, is demonstrated. decarbonylation with NEt3 to generate proceeded rapidly at rt, thereby allowing external-CO-free Pd-catalyzed carbonylation aryl/alkenyl halides triflates. reactivity the surrogate enabled rt significantly reduced quantities formate near-stoichiometric levels. obtained trichlorophenyl esters can be readily converted variety carboxylic acid derivatives in yields.

This account describes our findings on formic acid derivatives as practical carbon monoxide (CO) surrogates in synthetic organic chemistry. Among the known CO surrogates, are advantageous terms of their good availability, stability, and ease handling. We adopted two approaches to expand utility derivatives. One is use esters for reactions with alkenes based finding that substituted imidazoles can function ligands ruthenium-catalyzed hydroesterifications alkenes. The other approach involves...

Imidazole derivatives are revealed to be effective ligands in the Ru-catalyzed hydroesterification of alkenes using formates, affording one-carbon-elongated esters high yields. Further, intramolecular was successfully performed give lactones for first time. can contribute promote reaction as well suppress undesired decarbonylation formate. Toxic CO gas, a directing group, and large excess not required.

A variety of cyclic sulfonamides and sulfinamides could be selectively synthesized under Pd catalysis using haloarenes bearing amino groups a sulfur dioxide (SO2) surrogate. The amount base was key in determining the selectivity. Mechanistic studies revealed that were initially formed via an unprecedented formal insertion monoxide oxidized to presence iodide ion DMSO.

Because of its rare occurrence in modern sediments, as well the difficulty synthesizing it under low-temperature conditions laboratory, origin sedimentary dolomite has remained a long-standing enigma, often referred to “dolomite problem.” Recently, anaerobic microorganisms, such sulfate-reducing bacteria and methanogens, have been recognized for mediating precipitation. However, exact role microorganisms crystallization is still debate possible involvement fermenting not studied. In this...

The hydra-zone: first example of asymmetric InI catalysis had been developed. combined with a chiral semicorrin ligand (L*) is an effective catalyst for enantioselective allylation, crotylation, and α-chloroallylation hydrazones. In the two latter cases, CC bond formations proceeded high selectivity where both reactive aliphatic CCl aromatic OH bonds were tolerated. Detailed facts importance to specialist readers are published as "Supporting Information". Such documents peer-reviewed, but...

Various cyclic carbonyl compounds were concisely synthesized by carbonylative cyclization of haloarenes bearing nucleophilic moieties under Pd catalysis. A broad substrate scope and a feasible large-scale synthesis clearly demonstrate the high applicability reaction as general, user-friendly method for access to compounds.

Kinderleicht: Die Titelreaktion setzt die einfach zugängliche kristalline Verbindung N-Formylsaccharin als eine effektive CO-Quelle ein. Reaktionen laufen mit einem kleinen Überschuss der bei moderaten Temperaturen ab und konnten auf ein breites Spektrum von Arylbromiden angewendet werden. DMF=N,N-Dimethylformamid, dppb=1,4-Bis(diphenylphosphanyl)butan. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer...

Abstract A semi-empirical SCF MO method for valence electron systems, a modification of our previous made by introducing the zero-differential overlap approximation except one-center exchange integrals, is presented. The results calculated benzene, pyridine, pyrimidine and thiophene, parent molecules benzyne hetarynes, using this modified are compared with those obtained other calculations experiments. unstable intermediates treated in present paper benzyne, pyridynes, pyrimidyne thiophynes....

An ab initio SCF CI calculation was carried out for several lower states of O2 with various basis sets including diffuse pπ orbitals. Extensive calculations 2s and 2pπ functions show that the B 3Σu− state is essentially a valencelike as well c 1Σu−, C 3Δu, A 3Σu+ states, e.g., in X 3Σg− 〈z2〉 = 7.51 8.84 a.u. Various levels are compared existing theoretical results. The oscillator strength ← transition calculated to be 0.167 agreement experiment. qualitative discussion molecular dimension also made.

Abstract Using a semi-empirical ASMO SGF method for all valence electron systems, but modified to include one-center exchange integrals and an off-diagonal core integral as estimated by the approximation in our previous treatment, electronic structures of trans- cis-isomers butadiene, acrolein, glyoxal are calculated. The energy sequence molecular orbitals, charge distributions lone-pair orbitals π MO’s, distribution these compounds investigated. n–π* π–π* transition energies also presented;...

BACKGROUND: We studied the effects of advanced glycation end products (AGEs), which are known to accumulate in patients with diabetes, autoimmune diseases, or that smoke, on human trophoblasts. METHODS: First trimester chorionic villi 6–10 week gestation were obtained. Expression and localization receptor for AGEs (RAGE) was examined by western blotting immunohistochemistry. Macrophage inflammatory protein (MIP)-1α MIP-1β, regulated upon activation, normal T-cell expressed secreted (RANTES),...

Herein, we present a safe and practical methodology for synthesizing symmetrical sulfides using iodoarenes potassium metabisulfite (K2S2O5). While K2S2O5 is known as convenient sulfur dioxide surrogate, here it acts divalent source, pioneering its potential utility. The reaction exhibits wide substrate generality in which even highly bulky substrates can be applied to afford sterically congested sulfides.

Phosphine oxides were found to be efficient neutral coordinate-organocatalysts (NCOs) for the allylation of N-acylhydrazones. Among phosphine tested, a three carbon-tethered bisphosphine oxide (dppp dioxide) was most effective, and in presence dppp dioxide, less reactive aromatic [small alpha],[small beta]-unsaturated N-acylhydrazones underwent as well diastereoselective crotylation. Furthermore, polymer-supported also developed an effective immobilized NCO.

Abstract The mechanisms of the weak base‐catalyzed generation carbon monoxide (CO) and phenol from phenyl formate were investigated by experimental theoretical methods. Kinetic studies revealed a first‐order reaction in both base. was found to proceed an E2 α‐elimination pathway, which involves abstraction formyl proton formate, simultaneously generating CO phenoxide. rate affected substituents on polarity solvents, basicity bases. mechanistic insight obtained these permitted chemical...