552314-85-9Relevant academic research and scientific papers
Gold catalysis: Selectivity problems in hydroarylations with pyrroles
Hashmi, A. Stephen K.,Salathe, Ralph,Frey, Wolfgang
, p. 1648 - 1652 (2007)
Gold-catalyzed reactions of pyrrole derivatives with methyl vinyl ketone preferentially give rise to doubly substituted products, with an excess of methyl vinyl ketone even triple substitutions can be observed. This is independent of the electronic nature of substituents on the pyrrole ring, even substrates with electron-withdrawing acyl substituents in 1-2- or 3-position show this behavior. The NH group of the pyrrole ring may be unprotected, no competing hydroamination is observed. In an intramolecular competition experiment with a furan ring only the pyrrole ring reacted. The constitutions of the highly-substituted pyrroles were proven by NMR spectroscopy and one X-ray structure analysis. Control experiments show that Yb(OTf)3 does not catalyze these reactions, but Ag+ and H+ does. Contrary to pyrroles, under similar reaction conditions indoles show a clean monosubstitution reaction. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
AlCl3 as a powerful catalyst for the one-pot preparation of 1,1,3-triheteroaryl compounds
Shiri, Morteza,Zolfigol, Mohammad Ali,Ayazi-Nasrabadi, Roya
, p. 264 - 268 (2010)
A general and efficient procedure for the synthesis of 1,1,3-triheteroaryl compounds in good to excellent yield at room temperature is developed. The reaction proceeds via mixed Michael and Friedel-Crafts reactions of α,β-enals or α,β-enones and indoles, 2-methylfuran or 2-methylthiophene in the presence of a catalytic amount of AlCl3.
Metal–Organic Layers Hierarchically Integrate Three Synergistic Active Sites for Tandem Catalysis
Quan, Yangjian,Lan, Guangxu,Shi, Wenjie,Xu, Ziwan,Fan, Yingjie,You, Eric,Jiang, Xiaomin,Wang, Cheng,Lin, Wenbin
, p. 3115 - 3120 (2020/12/09)
We report the design of a bifunctional metal–organic layer (MOL), Hf12-Ru-Co, composed of [Ru(DBB)(bpy)2]2+ [DBB-Ru, DBB=4,4′-di(4-benzoato)-2,2′-bipyridine; bpy=2,2′-bipyridine] connecting ligand as a photosensitizer and Co(dmgH)2(PPA)Cl (PPA-Co, dmgH=dimethylglyoxime; PPA=4-pyridinepropionic acid) on the Hf12 secondary building unit (SBU) as a hydrogen-transfer catalyst. Hf12-Ru-Co efficiently catalyzed acceptorless dehydrogenation of indolines and tetrahydroquinolines to afford indoles and quinolones. We extended this strategy to prepare Hf12-Ru-Co-OTf MOL with a [Ru(DBB)(bpy)2]2+ photosensitizer and Hf12 SBU capped with triflate as strong Lewis acids and PPA-Co as a hydrogen transfer catalyst. With three synergistic active sites, Hf12-Ru-Co-OTf competently catalyzed dehydrogenative tandem transformations of indolines with alkenes or aldehydes to afford 3-alkylindoles and bisindolylmethanes with turnover numbers of up to 500 and 460, respectively, illustrating the potential use of MOLs in constructing novel multifunctional heterogeneous catalysts.
Alkylation of Indoles with α,β-Unsaturated Ketones using Alumina in Hexanes
Zhang, Xiong,Jones-Mensah, Ebenezer,Deobald, Jackson,Magolan, Jakob
supporting information, p. 5548 - 5551 (2019/11/19)
We evaluated the influence of solvent on the alumina-promoted C3-alkylation of indoles with α,β-unsaturated ketones. We found that lipophilic solvents were generally superior to hydrophilic ones with hexanes offering the 3-alkyl indole products in high yields. Thus, we demonstrate an inexpensive and procedurally simple new process that pairs acidic alumina with hexanes to achieve this important Michael alkylation. The substrate scope includes twenty-four examples with reaction yields ranging from 61 to 96%. (Figure presented.).
Ruthenium-Catalyzed Selective C?C Coupling of Allylic Alcohols with Free Indoles: Influence of the Metal Catalyst
Xia, Ying-Qi,Li, Chao,Liu, Man,Dong, Lin
supporting information, p. 5474 - 5478 (2018/03/29)
Versatile reactive activities of allyl alcohols with free indoles in C?H functionalization reactions were investigated. Direct alkylation or cascade cyclization reactions could be selectively controlled based on the catalyst system: Ru(PPh3)3Cl2 provided C3-substituted β-ketone indoles whereas [Ru(p-cymene)Cl2]2 yielded cyclized indoles.
A rapid and highly efficient Michael addition of methoxybenzenes and indoles to α,β-unsaturated ketones using BF3·OEt2 as a catalyst
Swetha,Raghavender Reddy,Madhu Babu,Meshram
supporting information, p. 4427 - 4431 (2017/10/30)
An efficient and general protocol is described for the Michael addition of α,β-unsaturated ketones with electron-rich arenes/indoles to give alkylated arenes/indoles under mild reaction condition at room temperature. Shorter reaction time, convenient and
Palladium(II) in electrophilic activation of aldehydes and enones: Efficient C-3 functionalization of indoles
Mohapatra, Swapna Sarita,Mukhi, Priyabrata,Mohanty, Anuradha,Pal, Satyanarayan,Sahoo, Aditya Omprakash,Das, Debjit,Roy, Sujit
supporting information, p. 5709 - 5713 (2015/09/29)
The regioselective C-3 alkylation of indoles with aldehydes and enones as electrophiles is catalyzed by a d8 late transition metal complex PdCl2(MeCN)2 at room temperature in the presence of air/moisture and in the absence
Heterobimetallic Pd-Sn catalysis: Michael addition reaction with C-, N-, O-, and S-nucleophiles and in situ diagnostics
Das, Debjit,Pratihar, Sanjay,Roy, Sujit
, p. 2430 - 2442 (2013/04/23)
An efficient Michael addition reaction of differently substituted enones with carbon, sulfur, oxygen, and nitrogen nucleophiles has been achieved by a new heterobimetallic "Pd-Sn" catalyst system. The nature of the catalytically relevant species and their
Highly effective and regioselective Michael addition of indoles to α,β-unsaturated ketones promoted by pentafluorophenylammonium triflate
Khaksar, Samad,Vahdat, Seyed Mohammad,Rezaee, Fatemeh
, p. 144 - 147 (2013/04/24)
A simple, inexpensive, environmentally friendly and efficient route for Michael addition of indoles to α,β-unsaturated ketones using pentafluorophenylammonium triflate (PFPAT) as a catalyst is described. Various indole derivatives were synthesized in good
Recyclable graphite oxide catalyzed Friedel-Crafts addition of indoles to α,β-unsaturated ketones
Vijay Kumar,Rama Rao
supporting information; experimental part, p. 5188 - 5191 (2011/10/12)
The Friedel-Crafts addition of indoles to α,β-unsaturated ketones, and nitro styrenes was studied with graphite oxide as catalyst. Various indole derivatives were synthesized in good to excellent yields. The preparation of graphite oxide catalyst from sim
