18648-70-9Relevant academic research and scientific papers
Sunlight-Driven Synthesis of Triarylethylenes (TAEs) via Metal-Free Mizoroki–Heck-Type Coupling
Onuigbo, Louis,Raviola, Carlotta,Di Fonzo, Andrea,Protti, Stefano,Fagnoni, Maurizio
, p. 5297 - 5303 (2018)
A protocol for the preparation of substituted triarylethylenes (TAEs) was developed by using arylazo sulfones as substrates in the presence of 1,1-diarylethylenes. The process took place efficiently in the absence of any (photo)catalyst upon exposure of the reaction mixture to (simulated) sunlight.
Pd-Catalyzed Coupling of N-Tosylhydrazones with Benzylic Phosphates: Toward the Synthesis of Di- or Tri-Substituted Alkenes
Zhang, Kena,Provot, Olivier,Alami, Mouad,Tran, Christine,Hamze, Abdallah
, p. 1249 - 1261 (2022/02/07)
This study shows that various di- and tri-substituted alkenes with high chemoselectivity were obtained in good to high yields by coupling N-tosylhydrazones (NTHs) with benzylic phosphates as electrophilic partners. The obtained new catalytic system consis
Microwave-assisted periselective annulation of triarylphosphenes with aldehydes and ketones
Du, Changle,Fu, Xingyang,Fu, Zhicheng,Luo, Yun,Xu, Jiaxi
, p. 9526 - 9537 (2020/12/15)
The reaction of diazo(aryl)methyl(diaryl)phosphine oxides with aldehydes and ketones generates benzo-δ-phosphinolactones in low to good yields with 1,1-diarylalk-1-enes as byproducts under microwave irradiation. Diazo(aryl)methyl(diaryl)phosphine oxides first undergo a Wolff rearrangement to form diaryl(aryl)phosphenes, which further react with aldehydes and ketones to afford benzo-δ-phosphinolactones and β-phosphinolactones. The latter are unstable under heating and fragment into the corresponding 1,1-diarylalk-1-enes and arylphosphine dioxides under reaction conditions. The arylphosphine dioxides become arylphosphonic acids during workup. The periselectivity in the annulation shows that the reaction of diaryl(aryl)phosphenes with most aldehydes and ketones favors phosphene phenyl participation in (4 + 2) annulation(2 + 2) annulation. This journal is
Immobilized Pd on Eggshell Membrane: A powerful and recyclable catalyst for Suzuki and Heck cross-coupling reactions in water
Wu, Shang,Jiang, Hongyan,Zhang, Hong,Zhao, Lianbiao,Yuan, Peilin,Zhang, Ying,Su, Qiong,Wang, Yanbin,Wu, Lan,Yang, Quanlu
, (2020/09/09)
A stable heterogeneous palladium catalysts, the waste eggshell membrane (ESM) anchored Pd complex, was synthesized by a simple and green technique. The catalyst obtained can display an outstanding catalytic activity for Suzuki and Heck coupling reactions in water media. The reactions of various aryl halides with aryl boronic acids and terminal alkenes provided the corresponding products in moderate to excellent yields. More importantly, this novel and efficient catalyst with high stability can be easily reused for at least twelve times with no decrease of the catalytic activity, performing an endurable and wide tolerance of the substrates. Facile synthesis, high catalytic activity, and recyclability make these catalysts interesting for further studies.
Polysubstituted ethylene compound as well as preparation method and application thereof
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Paragraph 0125-0129; 0275-0279, (2020/12/30)
The invention discloses a polysubstituted ethylene compound as well as a preparation method and application thereof. The invention particularly discloses a preparation method of a polysubstituted ethylene compound as shown in a formula III, which comprises the following step: in an organic solvent, carrying out reaction as shown in the specification on a compound as shown in a formula I and a compound as shown in a formula II in the presence of a palladium catalyst, a phosphine ligand and alkali to obtain the polysubstituted ethylene compound as shown in the formula III. The preparation methodcan be suitable for various types of substrates, and the configuration of double bonds is controllable.
Triarylalkenes from the site-selective reductive cross-coupling of benzophenones and aldehydes
Arkhypchuk, Anna I.,D'Imperio, Nicolas,Ott, Sascha
, p. 6030 - 6033 (2019/06/03)
PhP(Li)TMS converts benzophenones to phosphaalkenes which upon activation under oxidizing, basic conditions react with aromatic aldehydes under the formation of triarylalkenes. The one-pot reaction omits transition metals, proceeds at room temperature and precludes the formation of any homo-coupling products. Systematic substrate variations reveal reactivity patterns that are useful for the identification of ketone/aldehyde combinations that can be coupled in yields up to 80%.
Salicylic Acid-Catalyzed Arylation of Enol Acetates with Anilines
Felipe-Blanco, Diego,Gonzalez-Gomez, Jose C.
supporting information, p. 2773 - 2778 (2018/07/29)
α-Aryl ketones are both structure moieties commonly found in bioactive compounds and versatile synthetic intermediates for the preparation of drug-like molecules. An operationally simple and scalable protocol has been developed to prepare α-aryl ketones from readily available aromatic amines and enol acetates (or silyl enol ethers). This metal-free methodology features the use of salicylic acid as a convenient catalyst to promote the formation of aryl radicals from in-situ generated aryl diazonium salts, without demanding thermal or photochemical activation. The mild reaction conditions used are compatible with anilines substituted with diverse functionalities. Structural elaboration of some prepared α-aryl ketones was accomplished to illustrate their usefulness as building blocks. (Figure presented.).
Employing Water as the Hydride Source in Synthesis: A Case Study of Diboron Mediated Alkyne Hydroarylation
Rao, Santhosh,Joy, M. Nibin,Prabhu, Kandikere Ramaiah
, p. 13707 - 13715 (2018/11/30)
We present an approach to utilize water as the hydride source via Pd(II)/Pd(0) catalysis. As a case study, we have achieved a diboron mediated Pd(II)-catalyzed hydroarylation of alkynes using arylboronic acids. This approach not only complements conventional reactivity of Pd via Pd(0)/Pd(II) cycle for the hydroarylation but also utilizes water as the hydride source. We believe this would particularly be beneficial in utilizing water as a reagent.
Pd-catalyzed heck reactions of aryl bromides with 1,2-diarylethenes
Limberger, Jones,Poersch, Silvia,Monteiro, Adriano L.
experimental part, p. 1389 - 1394 (2012/04/23)
A catalytic system composed of Pd(OAc)2 and P(o-tol)3 was found to be effective for the Heck reaction of aryl bromides with diarylethylenes. Using K2CO3 as a base and DMF as a solvent, trisubstituted olefins were obtained in good to excellent yields. Aryl bromides containing an electron-withdrawing group in para position were less reactive for the Heck coupling reaction and gave substantial amount of homocoupling by-product suggesting that oxidative addition is not the rate-determining step. Electron withdrawing group substituent in the para position of stilbene affects the regioselectivity of the reaction. In this case, the phenyl group from the Ph-Pd complex migrates preferentially to the same carbon of the double bond to which the phenyl is bonded. Finally, a one pot sequential double Heck arylation of styrene was performed, giving trisubstituted olefin with an overall yield of 73percent.
Pd-catalyzed C=C double-bond formation by coupling of N-tosylhydrazones with benzyl halides
Xiao, Qing,Ma, Jian,Yang, Yang,Zhang, Yan,Wang, Jianbo
scheme or table, p. 4732 - 4735 (2009/12/24)
Pd-catalyzed reaction of N-tosylhydrazones with benzyl halides affords di- and trisubstituted olefins In high yields with excellent stereoselectivity. This coupling reaction Is supposed to proceed through a migratory insertion of Pd carbene species.
