查看更多>>摘要：A F reagent-mediated direct C-H carbamoylation of quinoxalin-2(1H)-ones has been developed. Under room temperature, a variety of isocyanides are employed to couple well with quinoxalin-2(1H)-ones affording 42 examples including 30 new compounds. This metal-free mild strategy tolerates a wide range of functional groups and shows environmental friendliness and practicality. (C) 2021 Elsevier Ltd. All rights reserved.
Kim, JaehwanPark, Se YeonJung, MyeongjinJang, Woo Cheol...
4页
查看更多>>摘要：The aza-Prins reaction of allylic imines triggered by N-2,2,2-trifluoroethylisatin ketimine is accomplished for the synthesis of spirooxindole derivatives involving trifluoromethyl group in the presence of TMSX. This cyclization reaction is operationally simple and proceeds under mild conditions using non-toxic reagents. Notably, while the previous our work could not be compatible with TMSX (X = Cl, I, etc) in one-pot process, this work describes successful aza-Prins reaction with TMSX (X = Cl, I, etc) via stepby-step process. (c) 2021 Elsevier Ltd. All rights reserved.
查看更多>>摘要：Azides and acetylenes are bio-orthogonal functional groups that can be readily coupled using copper(I)or ruthenium(II)- catalyzed 1,3-dipolar cycloaddition reactions. Using non-fluorescent aromatic azides and aromatic acetylenes, covering a range of electron rich and poor building blocks, the Huisgen cycloaddition afford 1,4-disubstituted or 1,5-disubstituted 1,2,3-triazoles. Using a combinatorial approach by running reaction in parallel in polypropylene 96-well plates we discovered several new fluorescent 1,2,3-triazoles scaffolds. These compounds show diverse interactions with biomolecules that could find applications in biology in, for example, fluorescence microscopy or biomolecule quantification. (c) 2021 Elsevier Ltd. All rights reserved.
查看更多>>摘要：A silver-mediated annulation between arylcarbamic acids and nitrosoarenes was developed, leading to phenazines in moderate to good yields with complexity and diversity. This procedure proceeded with the sequential ortho- C-H functionalization of arylcarbamic acids, insertion to nitroso group and decarboxylative annulation. (c) 2021 Elsevier Ltd. All rights reserved.
查看更多>>摘要：Allyl sulfones are synthesized via Cu-catalyzed ligand-free regioselective sulfonylation reaction from easily obtained alpha-methylstyrene derivatives and sulfonyl chlorides. This redox-neutral protocol also features a low-cost metal catalyst, broad substrate scope, good functional group tolerance and could be smoothly amplified to a gram scale. The allylic sulfone products can be used in diverse radical coupling reactions. (C) 2021 Elsevier Ltd. All rights reserved.
查看更多>>摘要：The reaction of N-1-sulfonyluracil derivatives bearing a 2-hydroxyethyl moiety at the 3-position with NaH under anhydrous conditions at room temperature affords the corresponding 2-oxazolidinone bearing the beta-enaminocarbonyl moiety. These products are useful diversifiable precursors toward various beta-amino acids and N-heterocyclic compounds. (C) 2021 Elsevier Ltd. All rights reserved.
查看更多>>摘要：A microwave mediated synthesis of 2-aminooxazoles at 150 degrees C was developed, providing products with a variety of functional groups. The reaction takes 5 min and provides product with a simple precipitation at moderate to good yields without the need for recrystallization or flash chromatography. (C) 2021 The Author(s). Published by Elsevier Ltd.
查看更多>>摘要：Cyanamides are an important class of molecules. This work describes a facile synthesis of disubstituted cyanamides. Here, readily accessible 1-cyano-1, 2-benziodoxol-3-(1H)-one (CBX) was applied as a stable electrophilic cyanation reagent. Diverse secondary amines were effectively cyanated. Moreover, secondary sulfonamides proved to be suitable substrates and were readily converted to N-alkyl(aryl)-N-aryl-sulfonyl-cyanamides, as the significant building blocks of the organic transformation. (c) 2021 Elsevier Ltd. All rights reserved.
查看更多>>摘要：A new type of spiro[pyrrolinyl-3,2'-oxindole] scaffolds were effectively prepared from an enantioselective Michael/cyclization between a crucial synthon of 3-(diphenylmethylene)-amino oxindole and acrolein catalyzed by a cinchona alkaloid in up to 99% total yield with up to 99% ee. Those spirooxindole aldehyde imines were reduced to new kinds of prolineamide like spirooxindole chiral amine organocatalysts. The reaction has been successfully scaled up to a gram scale and most typical organocatalysts were further purified up to 99% ee by recrystallization in their hydrochloride salts. (c) 2021 Published by Elsevier Ltd.
查看更多>>摘要：A convenient and one-pot synthetic method for the construction of indolo[2,1-a]isoquinolines is developed by the dehydrative cyclocondensation reactions of the easily available 2-hydroxymethyl anilines with 2-ethynylbenzaldehydes in DMSO in the presence of KOH and TBAI under air. (C) 2021 Elsevier Ltd. All rights reserved.
NSTL
Elsevier