Article
Chemistry, Organic
Hannah Siera, Mathis Kreuzahler, Christoph Woelper, Gebhard Haberhauer
Summary: Transition metal catalysis is a useful tool for C-C bond-forming reactions. Here, it is shown that gold(I)-catalyzed hydroalkynylation can selectively produce ynenamides, a relatively unknown type of molecule.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Paz Yepes, Angel L. Suarez-Sobrino, Miguel A. Rodriguez, Alfredo Ballesteros
Summary: The regio- and stereoselective carbosilylation reaction of tosylynamides with allylic trimethylsilanes is efficiently catalyzed by TMSNTf2 or HNTf2, resulting in high yields of (Z)-α-allyl-P-trimethylsilylenamides. Theoretical calculations reveal that the C-C triple bond of the ynamides is activated by the trimethylsilylium ion, leading to the formation of a P-trimethylsilylketenimonium cation. The subsequent transformations of the products demonstrate the synthetic utility of this reaction.
Article
Chemistry, Organic
Lucas Pages, Maxime Bouquin, Florian Jaroschik, Florian Monnier, Marc Taillefer
Summary: We present a simple protocol for the copper-catalyzed hydrothiolation of N-unsaturated precursors, enabling the room-temperature transformation of thiols into various thioethers and thioaminals with good selectivity. The use of a low loading of commercially available Cu(CH3CN)(4)PF6 catalyst facilitates the process.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Applied
Yue Zuo, Xingyuan Ye, Dongjie Jiang, Shuai Zhou, Mengyuan Yu, Guangke He
Summary: A chemo-selective copper(I)-catalyzed oxytrifluoromethylation of N-Boc-ynamides with TMSCF3 has been successfully achieved, giving the trifluoromethylated oxazolones in yields of 51-99%. The reaction proceeds at room temperature and tolerates a variety of functional groups including -X, -OMe, alkenyl, and other substituents. The resulting oxazolones provide access to alpha-CF3-substituted amines through decarboxylative reduction.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Organic
Hui Yang, Jie Wang, Can Jin, Xiaoqing Li, Xiangsheng Xu
Summary: Selective hydrofluorination of alkynes using aqueous HF was achieved using a gold catalyst and an amide directing group. The fluorination occurred at the position distal to the amino group for both aryl- and alkyl-substituted propargylamines.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Yuanjiu Xiao, Lei Tang, Tong-Tong Xu, Jian-Jun Feng
Summary: An atom-economical protocol for the efficient and highly selective trans-hydroarylation of ynamides with hydroxyarenes has been developed using B(C6F5)3 as the catalyst. This approach offers the advantages of readily available starting materials, low catalyst loading, mild reaction conditions, a broad substrate scope, ease of scale-up, and versatile functionalizations of the enamide products.
Article
Chemistry, Multidisciplinary
Pierre Hansjacob, Frederic R. Leroux, Vincent Gandon, Morgan Donnard
Summary: The palladium-catalyzed silylcyanation of ynamides is highly selective, producing exclusively tetrasubstituted 2-aminoacrylonitriles derivatives. The stereoselectivity is directly controlled by the nature of the substituent at the beta-position of the ynamide. The reaction is tolerant of various functional groups and provides a general method to access fully substituted 2-aminoacrylonitriles. The mechanism of this intriguing transformation is elucidated by computational study, and the range of 2-aminoacrylonitriles is expanded through postfunctionalization using the newly installed vinylsilane functionality.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Swetha Jos, Christine Tan, Pierre Thilmany, Alaa Saadane, Carla Slebodnick, Gwilherm Evano, Webster L. Santos
Summary: We have reported a tri-n-butyl phosphine catalyzed hydroboration reaction of ynamides, which provides regio- and stereo-selective formation of (Z)-beta-borylenamides in good yields. Surprisingly, a formal cis addition to the triple bond was observed, and this finding was confirmed by NMR and X-ray crystallography. P-31 NMR studies suggest that a zwitterionic vinylphosphonium intermediate plays a key role in the reaction mechanism. Furthermore, the resulting products were successfully transformed into beta-CF3 enamides via stereoretentive trifluoromethylation.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Daniel Mulryan, Jack Rodwell, Nicholas A. Phillips, Mark R. Crimmin
Summary: HF transfer reactions between organic substrates are potentially useful transformations. The development of catalytic systems that can promote both defluorination and fluorination steps in a single reaction sequence is reported. Mechanistic studies suggest that the Au(I) catalyst facilitates a catalytic network involving both concerted SNAr and hydrofluorination steps. This approach removes the need for direct handling of HF reagents in hydrofluorination and offers possibilities to manipulate the fluorine content of organic molecules through catalysis.
Article
Chemistry, Multidisciplinary
Yanyu Chen, Zhaobo Wang, Wutong Zhao, Shitao Sun, Lu Yang, Junpeng Zhang, Di Zhang, Maosheng Cheng, Bin Lin, Yongxiang Liu
Summary: This paper reports a chelation-controlled cycloisomerization reaction of tryptamine-ynamide catalyzed by Ag(i)/PPh3, which allows access to the spiro[indole-3,4'-piperidine] scaffold in a racemic and diastereoselective manner. Diastereoselective products are achieved through a chiron approach. Density functional theory calculations show that strong non-covalent interactions between the substrate and catalyst/ligand complex stabilize the formation of the spiroindoleninium intermediate via cation-pi-pi interactions.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Organic
Zhe Fan, Shao-Fei Ni, Jin-Yu Pang, Li-Ting Guo, Hao Yang, Ke Li, Cheng Ma, Ji-Kai Liu, Bin Wu, Jin-Ming Yang
Summary: A novel strategy for the formation of copper carbene and a Cu(I)-catalyzed cross-coupling protocol for the synthesis of 7-alkynyl cycloheptatrienes have been reported in this study.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Multidisciplinary Sciences
Kefeng Wang, Qingzhen Yu, Wenli Mao, Yuxin Zheng, Jing Xu, Yukun Wang
Summary: In this study, a copper(I)-catalyzed, highly selective and stereoselective radical trans-hydroboration of ynamides with N-heterocyclic carbene (NHC)-ligated borane was developed, leading to a series of trans-boryl enmides that can be conveniently transformed into various multi-substituted enamides. The method was found to be robust and scalable, and the mechanism of this unique reaction was studied and discussed.
Article
Chemistry, Organic
Yaowen Liu, Martin C. Dietl, Chunyu Han, Matthias Rudolph, Frank Rominger, Petra Kraemer, A. Stephen K. Hashmi
Summary: Multisubstituted alkenes can be efficiently synthesized by a gold-catalyzed acyloxyalkynylation reaction, which proceeds under mild conditions and accepts a wide range of substrates, resulting in high yields.
Article
Chemistry, Multidisciplinary
Wen-Feng Luo, Long-Wu Ye, Long Li, Peng-Cheng Qian
Summary: A method for the construction of valuable trans-3,4-diaryldihydrocoumarins via metal-free [4+2] annulation of ynamides with o-hydroxybenzyl alcohols has been developed, showing high regio- and diastereoselectivities, broad substrate scope, good functional group tolerance, and efficiency on a gram scale.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Aitor Maestro, Sebastien Lemaire, Syuzanna R. Harutyunyan
Summary: In this study, the first alkynylation of quinolones using terminal alkynes under mild reaction conditions is reported. The reaction is catalyzed by Cu(I) salts in the presence of a Lewis acid, which plays a crucial role in the reactivity of the system. Additionally, the enantioselective version of this transformation has been investigated and applied in the synthesis of the enantioenriched tetrahydroquinoline alkaloid cuspareine.
Article
Chemistry, Organic
Hai Huang, Guangke He, Guohao Zhu, Xiaolin Zhu, Shineng Qiu, Hongjun Zhu
JOURNAL OF ORGANIC CHEMISTRY
(2015)
Article
Chemistry, Multidisciplinary
Guohao Zhu, Wen-Chao Gao, Xuefeng Jiang
Summary: The Rh(I)-catalyzed cascade reaction enables the synthesis of diverse ortho silyl-substituted phenolics, leading to fully substituted aryne precursors through a one-step fluorosulfurylation. The silyl mask on alkynes not only suppresses undesired oxidation but also controls the selectivity of CO insertion. This straightforward method for accessing fully substituted arynes has been successfully applied for the efficient construction of polycyclic aromatic molecules.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
