Article
Biochemistry & Molecular Biology
Mohammad Shahidul Islam, Abdullah Saleh Alammari, Assem Barakat, Saeed Alshahrani, Matti Haukka, Abdullah Mohammed Al-Majid
Summary: Five new C-2-symmetric chiral ligands were synthesized from enantiopure amino alcohols, and used for Friedel-Crafts asymmetric alkylation. The bis(oxazolinyl)thiophene ligands showed higher efficiency in inducing asymmetric alkylation compared to bis(imidazolinyl)thiophene analogues.
Article
Chemistry, Organic
Esra Dundar, Cihangir Tanyeli
Summary: A series of chiral bifunctional squaramide organocatalysts were evaluated for their application in Friedel-Crafts alkylation of indoles, showing high enantioselectivity and moderate yields. This new asymmetric transformation provides a simple, efficient, clean, and environmentally friendly route for chemical synthesis.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Organic
Zeynep Dilsad Susam, Bilge Deniz Ozcan, Enis Kurtkaya, Erol Yildirim, Cihangir Tanyeli
Summary: In this study, bifunctional quinine-derived organocatalysts were used to catalyze the asymmetric Friedel-Crafts/S(N)2 domino reaction, resulting in enantiomerically enriched products. Density functional theory calculations were also performed to explain the stereoselectivity of the products.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Organic
Kosuke Nakashima, Sumire Hanamura, Aoi Imamura, Yasuyuki Matsushima, Shin-ichi Hirashima, Tsuyoshi Miura
Summary: This study investigates the asymmetric Friedel-Crafts alkylation of indoles with alpha,beta-unsaturated trifluoromethyl ketones using a squaramide organocatalyst. The squaramide organocatalyst efficiently promotes the reaction, yielding products with both indole motif and trifluoromethyl group in high yields and excellent enantioselectivities (up to 99% ee). The transformation of the obtained adduct to a chiral spiro indoline 3-one is also demonstrated.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Takanori Shibata, Mio Sasaki, Masafumi Kojima, Mamoru Ito
Summary: The chiral Ir(I)-catalyzed intermolecular reaction of N-carbamoylpyrrole and indole derivatives with alpha,beta-unsaturated carbonyl compounds proceeded with high enantioselectivity, yielding chirally functionalized pyrroles and indoles as formal C-H conjugate adducts. The reaction mechanism was further investigated through deuterium labeling experiments.
Article
Chemistry, Organic
Juan J. Rojas, Elena Torrisi, Maryne A. J. Dubois, Riashat Hossain, Andrew J. P. White, Giovanni Zappia, James J. Mousseau, Chulho Choi, James A. Bull
Summary: This paper reports a method for synthesizing 1,4-dioxanes and explores the catalytic mechanism of the reaction. The reaction exhibits high regio- and diastereoselectivity, and the resulting products serve as interesting motifs for drug discovery.
Article
Chemistry, Organic
Velu Saravanan, Arasambattu K. Mohanakrishnan
Summary: A one-pot synthesis of aryl- and heteroaryl-annulated carbazoles was achieved from 2/3-bromomethylindoles, along with a bis-domino reaction of 2,5-bis(bromomethyl)pyrrole with selected heteroarenes. The synthesized thienocarbazoles and thienodibenzofurans were successfully utilized for a second-generation domino reaction.
SYNTHESIS-STUTTGART
(2021)
Article
Chemistry, Multidisciplinary
Ning Li, Wenjing Lu, Weizhi Gu, Kuiliang Li, Jindong Li, Yangmian Lu, Zhenggen Zha, Zhiyong Wang
Summary: An asymmetric Michael/hemiketalization reaction was developed between isatin-derived beta, gamma-unsaturated alpha-ketoesters and 4-hydroxycoumarins in aqueous media. A series of chiral spirooxindole derivatives with an all-carbon quaternary stereogenic center were obtained in high yields (up to 93%) and excellent enantioselectivities (up to 98%).
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Jin Jiaping, Alemayehu Gashaw Woldegiorgis, Xufeng Lin
Summary: Here, we report an enantioselective protocol for the chiral phosphoric acid-catalyzed addition of 3-arylisoxazol-5-amines to highly reactive 3-methide-3H-pyrroles. This protocol provides a diverse range of heterotriarylmethanes bearing an amino acid moiety in good yields (up to 97%) and high enantioselectivities (up to 93% ee) under mild conditions. The utilization of a chiral spirocyclic phosphoric acid is crucial in converting the initial 1H-pyrrol-3-yl carbinols into reactive 3-methide-3H-pyrroles and achieving the desired enantioselective transformation.
Article
Chemistry, Applied
Feng Ma, Xian-Tao Wu, Le-Wei Miao, Fuxing Sun, Yi-Jun Jiang, Peng Chen
Summary: A general, efficient, and regioselective protocol for the synthesis of trifluoromethylated bis(carbazolyl)methanes has been developed. This metal-free transformation proceeds smoothly under air atmosphere and has a broad scope for both reaction partners. This method can also be extended to the synthesis of difluoromethylated and chlorodifluoromethylated bis(carbazolyl)methanes.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Engineering, Chemical
Haonan Zhang, Haotian Zhang, Minli Tao, Wenqin Zhang
Summary: The study synthesized three functionalized polyacrylonitrile fiber catalysts through amination and quaternization, and explored their catalytic activity in the Friedel-Crafts alkylation reaction. The results showed that one of the catalysts exhibited the highest catalytic activity in the reaction and had strong recycling performance. Additionally, this catalyst showed excellent catalytic activity for most aromatic aldehydes containing moderate electron donating groups.
CHINESE JOURNAL OF CHEMICAL ENGINEERING
(2022)
Article
Chemistry, Multidisciplinary
Bei Zhou, Zhuang Ma, Asma M. Alenad, Carsten Kreyenschulte, Stephan Bartling, Matthias Beller, Rajenahally Jagadeesh
Summary: A general method for cobalt-catalysed CH-alkylation of indoles with alcohols is reported, which allows the easy synthesis of substituted and functionalized indoles in good yields. The resulting products are an interesting class of heterocyclic compounds widely used in organic synthesis and medicinal chemistry.
Article
Chemistry, Inorganic & Nuclear
Zubi Sadiq, Ambreen Ghani, Shahida Shujaat, Erum Akbar Hussain, Siham A. Alissa, Munawar Iqbal
Summary: In this study, structurally diverse improvements were made to bis(indolyl)methanes using a multicomponent approach, where SiO2-KHSO4 catalyst was used. The reaction time was significantly reduced and high yields were achieved for the synthesized compounds.
INORGANIC CHEMISTRY COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Hua-Qi Wang, Shu-Bin Mou, Wen Xiao, Huan Zhou, Xu-Dong Hou, Su-Jing Wang, Qian Wang, Jiali Gao, Zhiyi Wei, Lijun Liu, Zheng Xiang
Summary: CylK is a key enzyme that catalyzes the formation of the cylindrocyclophane scaffold through Friedel-Crafts alkylation reactions, exhibiting regioselectivity and stereospecificity. This study proposes a concerted double-activation mechanism to explain the enzymatic alkylation with regioselectivity and stereospecificity, based on crystal structures, free energy simulations, and site-directed mutagenesis experiments.
Article
Chemistry, Organic
Aparna Tyagi, Jabir Khan, Naveen Yadav, Rina Mahato, Chinmoy Kumar Hazra
Summary: A novel and effective Bronsted acid-catalyzed chemoselective synthesis of bis(indolyl)alkanes and 3-alkyl indoles is reported. The selectivity of two significant indole derivatives is attained by allowing the same substrates to go through divergent reaction routes catalyzed by different catalysts.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
