94532-99-7Relevant academic research and scientific papers
A Convenient Formal [4+2] Heterocylization Route to Bis(triflyl)tetrahydroquinolines
Lázaro-Milla, Carlos,Almendros, Pedro
, p. 13534 - 13538 (2021/08/13)
We report the sustainable and efficient synthesis of a new type of quinoline derivatives bearing one or two SO2CF3 groups. The protocol is metal-, catalyst- and irradiation-free, involves the use of readily available and stable precursors, and avoids the formation of side products. Also, the mild conditions of the process allow the tolerance of a wide range of functional groups.
Modulation of imine chemistry with intramolecular hydrogen bonding: Effects from ortho-OH to NH
Chen, Hang,Feng, Zelin,Jia, Shuaipeng,You, Lei
, (2020/03/24)
Salicylaldehyde derivatives and their imines are important building blocks in organic and supramolecular chemistry. In an effort to expand structural diversity in the current work we changed ortho-OH in salicylaldehyde to NH of amide/sulfonamide and investigated the effect of resulting intramolecular hydrogen bonds on imine dynamic covalent chemistry (DCC). A suite of ortho-aminobenzaldehydes were readily synthesized, and X-ray and NMR data validated the existence of NH?O intramolecular hydrogen bonds. The formation and exchange of imines were then studied in acetonitrile, and the acidity of OH/NH significantly influenced the thermodynamics and kinetics of imine reactions. Furthermore, the role of OH/NH?N hydrogen bonds on imines was elucidated by the shift of aldehyde exchange equilibrium. Finally, the formation of imines was achieved in aqueous solutions. The mechanistic insights could pave the way for future applications in assembly and labelling.
Enantioselective Synthesis of Complex Fused Heterocycles through Chiral Phosphoric Acid Catalyzed Intramolecular Inverse-Electron-Demand Aza-Diels–Alder Reactions
Jarrige, Lucie,Gandon, Vincent,Masson, Géraldine
, p. 1406 - 1413 (2020/01/24)
A stable asymmetric intramolecular Povarov reaction has been established to provide an efficient method to access structurally diverse trans,trans-trisubstituted tetrahydrochromeno[4,3-b]quinolines in high stereoselectivities of up to >99:1 diastereomeric
Visible-Light-Driven Neutral Nitrogen Radical Mediated Intermolecular Styrene Difunctionalization
Zhao, Quan-Qing,Li, Man,Xue, Xiao-Song,Chen, Jia-Rong,Xiao, Wen-Jing
supporting information, p. 3861 - 3865 (2019/05/24)
A neutral nitrogen radical-mediation strategy, wherein the existing N-H moiety of substrates serves as a neutral nitrogen radical precursor to enable room-temperature intermolecular radical difunctionalization of styrenes under photoredox catalysis, is reported. The reaction shows high functional group tolerance and substrate scope with respect to both components, giving the corresponding products with generally good yields. Preliminary control experiments and DFT calculations are performed to explain the reaction mechanism.
NHC-Catalyzed Chemoselective Reactions of Enals and Aminobenzaldehydes for Access to Chiral Dihydroquinolines
Wu, Shuquan,Liu, Changyi,Luo, Guoyong,Jin, Zhichao,Zheng, Pengcheng,Chi, Yonggui Robin
, p. 18410 - 18413 (2019/11/14)
An N-heterocyclic carbene (NHC)-catalyzed reaction between α-bromoenals and 2-aminoaldehydes has been developed. Key steps include chemoselective reaction of the NHC catalyst with one of the aldehyde substrates (the bromoenal) to eventually generate an α,β-unsaturated acylazolium intermediate. Addition of the nitrogen atom of aminoaldehyde to the unsaturated azolium ester intermediate followed by intramolecular aldol reaction, β-lactone formation, and decarboxylation leads to chiral dihydroquinolines with high optical purity. The dihydroquinoline products, which are quickly prepared by using this method, can be readily transformed into a diverse set of functional molecules such as pyridines and chiral piperidines.
Direct Access to 9-Chloro-1 H-benzo[ b]furo[3,4- e]azepin-1-ones via Palladium(II)-Catalyzed Intramolecular syn-Oxypalladation/Olefin Insertion/sp2-C-H Bond Activation Cascade
Karuppasamy, Muthu,Vachan,Vinoth, Perumal,Muthukrishnan, Isravel,Nagarajan, Subbiah,Ielo, Laura,Pace, Vittorio,Banik, Subrata,Maheswari, C. Uma,Sridharan, Vellaisamy
supporting information, p. 5784 - 5788 (2019/08/26)
An efficient Pd(II)-catalyzed cascade approach was established for the synthesis of 9-chloro-1H-benzo[b]furo[3,4-e]azepin-1-ones starting from N-propargyl arylamines having a pendant α,β-unsaturated ester scaffold. The mechanism of this sequential process involved intramolecular syn-oxypalladation followed by olefin insertion and ortho sp2-C-Cl bond formation reactions. This high atom- and step-economical cascade sequence generated two heterocycle rings and three new bonds in a single synthetic operation.
Straightforward and Sustainable Synthesis of Sulfonamides in Water under Mild Conditions
Eid, Nadim,Karamé, Iyad,Andrioletti, Bruno
supporting information, p. 5016 - 5022 (2018/09/14)
Ideally, a sustainable chemical synthesis should involve the use of non-toxic solvents and reactants, easy separations and purification by energy-efficient processes. In this context, reconsidering the synthesis of widely used drugs is especially timely and should allow important benefits to be obtained in terms of environmental impact. Sulfonamides are pertinent as their synthesis generally requires the use of toxic and/or hard-to-remove solvents such as dichloromethane, DMF and DMSO. In addition, toxic and highly reactive sulfur-containing sources such as sulfonyl chloride are often involved and coupled with amines. Moreover, the latter may exhibit some toxicity and are generally difficult to purify. Herein, we disclose the unprecedented and sustainable synthesis of sulfonamides by using sodium sulfinate as a commercial and stable sulfur source and nitroarenes as the nitrogen-containing reactant. In addition, under the optimized conditions only water is used as a “green” solvent and the products are collected by simple filtration.
Iridium- and Rhodium-Catalyzed Directed C-H Heteroarylation of Benzaldehydes with Benziodoxolone Hypervalent Iodine Reagents
Grenet, Erwann,Waser, Jér?me
, p. 1473 - 1476 (2018/03/09)
The C-H heteroarylation of benzaldehydes with indoles and pyrroles was realized using the benziodoxolone hypervalent iodine reagents indole- and pyrroleBX. Functionalization of the aldehyde C-H bond using either an o-hydroxy or amino directing group and catalyzed by an iridium or a rhodium complex allowed the synthesis of salicyloylindoles and (2-sulfonamino)benzoylindoles, respectively, with good to excellent yields (74-98%). This new transformation could be carried out under mild conditions (rt to 40 °C) and tolerated a broad range of functionalities, such as ethers, halogens, carbonyls, or nitro groups.
Divergence in Ynone Reactivity: Atypical Cyclization by 3,4-Difunctionalization versus Rare Bis(cyclization)
Alcaide, Benito,Almendros, Pedro,Lázaro-Milla, Carlos,Delgado-Martínez, Patricia
, p. 8186 - 8194 (2018/06/15)
Functionalized ynones can be activated by Tf2C=CH2, which was generated in situ, to form zwitterionic species. These species were trapped in an intramolecular fashion by several nucleophiles to generate two major types of triflones in a divergent manner. Through fine-tuning of the reaction temperature, bis(triflyl)-6-membered- or (triflyl)-5-membered-fused-heterocycles were achieved in reasonable yields in a totally selective manner. In this way, bis(triflyl)flavones, bis(triflyl)thioflavones, bis(triflyl)selenoflavones, (triflyl)benzothienopyrans, (triflyl)benzoselenophenopyrans, (triflyl)vinyl aurones, and (triflyl)pyranoindoles were constructed. Conceivable mechanistic pathways were suggested on the basis of the isolation of several intermediates and the results from control experiments.
Palladium-catalyzed oxidative cyclization of aniline-tethered alkylidenecyclopropanes with O2: a facile protocol to selectively synthesize 2- and 3-vinylindoles
Cao, Bo,Simaan, Marwan,Marek, Ilan,Wei, Yin,Shi, Min
, p. 216 - 219 (2016/12/27)
A novel palladium-catalyzed oxidative cyclization of aniline-tethered alkylidenecyclopropanes using molecular oxygen as the terminal oxidant through β-carbon elimination of aminopalladation intermediates is disclosed. The reaction opens up an effective way to obtain a series of 2- and 3-vinylindoles which are important synthetic intermediates in many natural indole derivatives.
