10075-48-6Relevant academic research and scientific papers
Palladium-catalyzed C-H ethoxycarbonyldifluoromethylation of electron-rich heteroarenes
Shao, Changdong,Shi, Guangfa,Zhang, Yanghui,Pan, Shulei,Guan, Xiaohong
, p. 2652 - 2655 (2015)
The first Pd-catalyzed C-H ethoxycarbonyldifluoromethylation with BrCF2CO2Et has been developed. The use of a bidentate phosphine ligand (Xantphos) is critical for the reaction to occur. A variety of electron-rich heteroarenes, including indoles, furans, thiophenes, and pyrroles, can be ethoxycarbonyldifluoromethylated in moderate to excellent yields. The reactions take place at the C-H bonds adjacent to the heteroatoms with high regioselectivity. This method provides a new protocol for the introduction of difuoroalkyl groups into electron-rich heteroarenes.
Direct oxidative coupling of N-acetyl indoles and phenols for the synthesis of benzofuroindolines related to phalarine
Tomakinian, Terry,Guillot, Rgis,Kouklovsky, Cyrille,Vincent, Guillaume
, p. 11881 - 11885 (2014)
Inspired by the biogenetic synthesis of benzofuro-indoline-containing natural products, we designed an oxidative coupling between phenol and N-acetyl indoles. This straightforward and direct radical process, mediated by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and FeCl 3 allowed the regioselective synthesis of benzofuro[3,2-b]indolines, whose structure is found in the natural product phalarine.
Synthesis of Pyrido[2,3-b]indole Derivatives via Rhodium-Catalyzed Cyclization of Indoles and 1-Sulfonyl-1,2,3-triazoles
An, Yuehui,Chen, Yidian,Duan, Shengguo,Li, Chuan-Ying,Xu, Ze-Feng,Xue, Bing,Zhang, Wan
, (2020)
Acyloxy-substituted α,β-unsaturated imines generated in situ from triazoles can act as aza-[4 C] synthons and be trapped by indoles in a stepwise [4 + 2] cycloaddition reaction, thus providing rapid access to valuable pyrido[2,3-b]indoles in high yields. Attractive features of this reaction system include operational simplicity, readily available substrates, construction of sterically demanding quaternary centers, and convenient derivatization using triflate. (Figure presented.).
Asymmetric Synthesis of Furo[3,4-b]indoles by Catalytic [3+2] Cycloaddition of Indoles with Epoxides
Chen, Weiliang,Xia, Yong,Lin, Lili,Yuan, Xiao,Guo, Songsong,Liu, Xiaohua,Feng, Xiaoming
, p. 15104 - 15107 (2015)
A highly efficient N,N′-dioxide-NiII catalyst system for the catalytic [3+2] cycloaddition of indoles with epoxides through C-C cleavage of oxiranes was accomplished under mild conditions. It provided a promising approach for chiral furo[3,4-b]indoles in up to 98 % yield with up to 91 % enantiomeric excess (ee) and >95:5 diastereomeric ratio (d.r.). A promising approach: Catalytic de-aromatic [3+2] cycloaddition of indoles with epoxides by C-C cleavage of oxiranes is accomplished by using a highly efficient N,N′-dioxide-NiII catalyst system. A range of chiral furo[3,4-b]indoles is obtained with high enantiomeric excesses and diastereomeric ratios.
Organocatalytic Formal (3 + 2) Cycloaddition toward Chiral Pyrrolo[1,2- a]indoles via Dynamic Kinetic Resolution of Allene Intermediates
Bai, Jian-Fei,Zhao, Lulu,Wang, Fang,Yan, Fachao,Kano, Taichi,Maruoka, Keiji,Li, Yuehui
, p. 5439 - 5445 (2020)
We report the chiral phosphoric acid catalyzed formal (3 + 2) cycloaddition of 3-substituted 1H-indoles and propargylic alcohols containing a functional directing group (p-NHAc or p-OH). This work represents a straightforward method to synthesize chiral pyrrolo[1,2-a]indole bearing a tetrasubstituted carbon stereocenter. The reaction proceeds smoothly with a wide array of substrate tolerance to deliver various chiral pyrrolo[1,2-a]indoles in up to 93percent yield and 98percent ee. The utility of this method is highlighted by the diverse transformations of the products into various indole derivatives.
Enantioselective 2-alkylation of 3-substituted indoles with dual chiral lewis acid/hydrogen-bond-mediated catalyst
Zhou, Zijun,Li, Yanjun,Gong, Lei,Meggers, Eric
, p. 222 - 225 (2017)
A chiral-at-metal bis-cyclometalated iridium complex combines electrophile activation via metal coordination with nucleophile activation through hydrogen bond formation. This new bifunctional chiral Lewis acid/hydrogenbond-mediated catalyst permits the challenging enantioselective 2-alkylation of 3-substituted indoles with α, β-unsaturated 2-acyl imidazoles in up to 99% yield and with up to 98% enantiomeric excess at a catalyst loading of 2 mol %. As an application, the straightforward synthesis of a chiral pyrrolo- [1, 2-a]indole is demonstrated.
Rhenium(I)-Catalyzed C-Methylation of Ketones, Indoles, and Arylacetonitriles Using Methanol
Shee, Sujan,Kundu, Sabuj
, p. 6943 - 6951 (2021/05/29)
A ReCl(CO)5/MeC(CH2PPh2)3 (L2) system was developed for the C-methylation reactions utilizing methanol and base, following the borrowing hydrogen strategy. Diverse ketones, indoles, and arylacetonitriles underwent mono-and dimethylation selectively up to 99% yield. Remarkably, tandem multiple methylations were also achieved by employing this catalytic system.
Constructing Saturated Guanidinum Heterocycles by Cycloaddition of N-Amidinyliminium Ions with Indoles
Allred, Tyler K.,Shaghafi, Michael B.,Chen, Pan-Pan,Tran, Quan,Houk,Overman, Larry E.
supporting information, p. 7618 - 7623 (2021/10/12)
We report that structurally complex guanidinium heterocycles can be prepared in one step by regio- and stereoselective [4 + 2]-cycloadditions of N-amidinyliminium ions with indoles or benzothiophene. In contrast to reactions of these heterodienes with alkenes, density functional theory (DFT) calculations show that these cycloadditions take place in a concerted asynchronous fashion. The [4 + 2]-cycloaddition of N-amidinyliminium ions (1,3-diaza-1,3-dienes) with indoles and benzothiophene are distinctive, as related [4 + 2]-cycloadditions of N-acyliminium ions (1-oxa-3-aza-1,3-dienes) are apparently unknown.
Selective Oxidative Cleavage of 3-Methylindoles with Primary Amines Affording Quinazolinones
He, Junhui,Dong, Jianyu,Su, Lebin,Wu, Shaofeng,Liu, Lixin,Yin, Shuang-Feng,Zhou, Yongbo
supporting information, p. 2522 - 2526 (2020/04/09)
A selective functionalization of C-C-C bonds toward N-C-O bonds is realized by an n-Bu4NI-catalyzed reaction of 3-methylindoles with primary amines using TBHP as the unique oxidant. The systematic process involves oxygenation, nitrogenation, ring-opening, and recyclization, affording a broad range of quinazolinones in good to excellent yields.
Ruthenium Pincer Complex Catalyzed Selective Synthesis of C-3 Alkylated Indoles and Bisindolylmethanes Directly from Indoles and Alcohols
Biswas, Nandita,Sharma, Rahul,Srimani, Dipankar
supporting information, p. 2902 - 2910 (2020/06/03)
Herein, we presented Ru-SNS complex that serves as a useful catalyst for C-3 alkylation of 1H-indoles with various aliphatic primary and secondary alcohols including cyclic alcohols as well as benzylic alcohols. The selective synthesis of bisindolylmethane derivatives is also achieved from the same set of indole and alcohol just by altering the reaction parameters. Furthermore, the sustainable synthesis of C-3 alkylated indoles directly from 2-(2-nitrophenyl)ethan-1-ol and alcohols catalysed by a Ru-complex via “borrowing hydrogen” strategy is reported. This protocol provides an atom-economical sustainable route to access structurally important compounds like arundine, vibrindole A and tryptamine based derivatives. (Figure presented.).
