19797-08-1Relevant articles and documents
“TPG-lite”: A new, simplified “designer” surfactant for general use in synthesis under micellar catalysis conditions in recyclable water
Thakore, Ruchita R.,Takale, Balaram S.,Hu, Yuting,Ramer, Selene,Kostal, Jakub,Gallou, Fabrice,Lipshutz, Bruce H.
, (2021/04/22)
Using the oxidized, carboxylic acid-containing form of MPEG-750, esterification with racemic vitamin E affords a new surfactant (TPG-lite) that functions as an enabling, nanoreactor-forming amphiphile for use in many types of important reactions in synthesis. The presence of a single ester bond is suggestive of simplified treatment as a component of (eventual) reaction waste water, after recycling. Many types of reactions, including aminations, Suzuki-Miyaura, SNAr, and several others are compared directly with TPGS-750-M, leading to the conclusion that TPG-lite can function as an equivalent nanomicelle-forming surfactant in water. Prima facie evidence amassed via DLS and cryo-TEM analyses support these experimental observations. In silico evaluations of the aquatic toxicity and carcinogenicity of TPG-lite indicate that it is safe to use.
Chemoselective Hydrogenation of Olefins Using a Nanostructured Nickel Catalyst
Klarner, Mara,Bieger, Sandra,Drechsler, Markus,Kempe, Rhett
supporting information, p. 2157 - 2161 (2021/05/21)
The selective hydrogenation of functionalized olefins is of great importance in the chemical and pharmaceutical industry. Here, we report on a nanostructured nickel catalyst that enables the selective hydrogenation of purely aliphatic and functionalized olefins under mild conditions. The earth-abundant metal catalyst allows the selective hydrogenation of sterically protected olefins and further tolerates functional groups such as carbonyls, esters, ethers and nitriles. The characterization of our catalyst revealed the formation of surface oxidized metallic nickel nanoparticles stabilized by a N-doped carbon layer on the active carbon support.
PROCESS FOR THE SYNTHESIS OF N-SUBSTITUTED LACTAMS AND AMIDES
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Paragraph 0033, (2021/06/22)
A process for the synthesis of N-alkylated lactams via reductive alkylation. The process of the present disclosure may be conducted by the addition of an aldehyde to a lactam in the presence of a catalyst under a reducing atmosphere.
Environmentally responsible, safe, and chemoselective catalytic hydrogenation of olefins: ppm level Pd catalysis in recyclable water at room temperature
Gallou, Fabrice,Gao, Eugene S.,Lipshutz, Bruce H.,Takale, Balaram S.,Thakore, Ruchita R.
supporting information, p. 6055 - 6061 (2020/10/14)
Textbook catalytic hydrogenations are typically presented as reactions done in organic solvents and oftentimes under varying pressures of hydrogen using specialized equipment. Catalysts new and old are all used under similar conditions that no longer reflect the times. By definition, such reactions are both environmentally irresponsible and dangerous, especially at industrial scales. We now report on a general method for chemoselective and safe hydrogenation of olefins in water using ppm loadings of palladium from commercially available, inexpensive, and recyclable Pd/C, together with hydrogen gas utilized at 1 atmosphere. A variety of alkenes is amenable to reduction, including terminal, highly substituted internal, and variously conjugated arrays. In most cases, only 500 ppm of heterogeneous Pd/C is sufficient, enabled by micellar catalysis used in recyclable water at room temperature. Comparison with several newly introduced catalysts featuring base metals illustrates the superiority of chemistry in water.
N-Alkylation of N-trimethylsilyl derivatives of lactams, amides, and imides with alkyl sulfonates
Baukov, Yu. I.,Kramarova, E. P.,Negrebetsky, Vad. V.,Shagina, A. D.,Shipov, A. G.,Tarasenko, D. V.
, p. 398 - 400 (2020/04/15)
The reaction of N-trimethylsilyl derivatives of amides and imides with alkyl sulfonates on heating affords the corresponding N-alkyl derivatives and trimethylsilyl sulfonates.
Reduction of alkenes catalyzed by copper nanoparticles supported on diamond nanoparticles
Dhakshinamoorthy, Amarajothi,Navalon, Sergio,Sempere, David,Alvaro, Mercedes,Garcia, Hermenegildo
supporting information, p. 2359 - 2361 (2013/07/05)
Copper nanoparticles (Cu NPs) supported on diamond nanoparticles (D NPs) previously purified by Fenton treatment (Cu/D) followed by annealing with hydrogen (Cu/DH) are highly efficient and reusable heterogeneous catalysts for hydrogenation of styrene to ethylbenzene with the minimum productivity value of 30617 cycles. The Royal Society of Chemistry.
Hydroamination of unactivated alkenes catalyzed by novel platinum(II) N -heterocyclic carbene complexes
Cao, Peng,Cabrera, Jose,Padilla, Robin,Serra, Daniel,Rominger, Frank,Limbach, Michael
experimental part, p. 921 - 929 (2012/04/10)
Cationic platinum(II) complexes with bi- or tridentate (pincer) functionalized NHC ligands were found to be catalytically active in the hydroamination of unactivated alkenes. In some cases, the presence of water had an activating effect on the complexes. Reactions with the N-nucleophilic substrate morpholine led to a noncatalytic reaction in which the deprotonation product of the key cationic β-aminoalkyl platinum complex could be isolated and characterized. Surprisingly, attempted protonation of this complex did not give the expected N-alkylated product, indicating either the thermodynamic unfavorability of C-Pt bond cleavage or its kinetic inertness.
Ammonium formate/palladium on carbon: A versatile system for catalytic hydrogen transfer reductions of carbon-carbon double bonds
Paryzek, Zdzislaw,Koenig, Hanna,Tabaczka, Bartlomiej
, p. 2023 - 2026 (2007/10/03)
Various carbon-carbon double bonds in olefins and α,β -unsaturated ketones were effectively reduced to the corresponding alkanes and saturated ketones, using ammonium formate as a hydrogen transfer agent in the presence of Pd/C as catalyst in refluxing methanol.
Toxicity screening of N-alkylazacycloheptan-2-one derivatives in cultured human skin cells: Structure-toxicity relationships
Ponec,Haverkort,Soei,Kempenaar,Brussee,Bodde
, p. 738 - 741 (2007/10/02)
A number of N-alkylazacycloheptan-2-one derivatives, with the hydrocarbon chain lengths systematically varied from C2 to C16, were tested for their possible skin toxic effects. For this purpose, three in vitro cytotoxicity assays were used: (1) inhibition of proliferation of cultured human fibroblasts and keratinocytes: (2) inhibition of collagen contraction by human fibroblasts; and (3) cell morphology changes in confluent cultures of human fibroblasts and keratinocytes. With all assays used, the toxicity of N-alkylazacycloheptan-2-one derivatives increased from C2 to C8, remained constant at a hydrocarbon chain length between C8 and C14, and subsequently decreased with increasing alkyl chain length. A similar trend has been observed for flux enhancement of nitroglycerine in the presence of these N-alkylazacycloheptan-2-one derivatives, suggesting that with these compounds a parallelism exists between skin cell toxicity and penetration enhancing capacity. Since for practical use it is preferable to find a balance between skin toxicity and the penetration enhancement effect of a particular enhancer, it would be advisable to do QSAR studies of this kind with a number of congeners of a particular compound in order to optimize the choice. In this particular case, further modification of the N-alkylazacycloheptan-2-one structure might lead to an even better choice than the often propagated dodecyl derivative.
