17150-61-7Relevant articles and documents
Electrochemical oxidative cyclization of: N -allylcarboxamides: Efficient synthesis of halogenated oxazolines
He, Yanyang,Liu, Chenwei,Wu, Xiao-Feng,Yin, Yanzhao,Yin, Zhiping
supporting information, p. 663 - 667 (2022/01/22)
Herein, we reported an efficient and sustainable intramolecular electrochemical cyclization of N-allylcarboxamides for the synthesis of various halogenated oxazolines. This method was conducted in a simple undivided cell by employing lithium halogen salts
Metal-free Photochemical Atom Transfer Radical Addition (ATRA) of BrCCl3 to Alkenes
Nikitas, Nikolaos F.,Voutyritsa, Errika,Gkizis, Petros L.,Kokotos, Christoforos G.
supporting information, p. 96 - 101 (2021/01/04)
A simple, photochemical, and metal-free protocol for the atom transfer radical addition (ATRA) of bromotrichloromethane onto various alkenes is described. Among a range of organic molecules, phenylglyoxylic acid proved to be the most suitable photoinitiator to promote a sustainable process for the addition of bromotrichloromethane to olefins. This photochemical atom transfer radical protocol can be expanded into a wide substrate scope of aliphatic olefins bearing various functional groups, leading to the corresponding products in good to excellent yields.
Nickel-Catalyzed Four-Component Carbocarbonylation of Alkenes under 1 atm of CO
Zhou, Minqi,Zhao, Hai-Yang,Zhang, Shu,Zhang, Yanxia,Zhang, Xingang
supporting information, p. 18191 - 18199 (2020/12/04)
Transition-metal-catalyzed carbonylation is one of the most straightforward strategies to prepare carbonyl compounds. However, compared to well-established noble-metal-catalyzed carbonylation reactions, analogue coupling via base-metal, nickel catalysis has received less attention because of the easy formation of highly toxic and unreactive Ni(CO)4 species between Ni(0) and CO. To date, the use of inexpensive and widely available carbon monoxide (CO) gas for nickel-catalyzed carbonylation reaction remains challenging, and nickel-catalyzed four-component carbonylative reaction has not been reported yet. Here, we report a highly selective nickel-catalyzed four-component carbocarbonylation of alkenes under 1 atm (1 atm) of CO gas to efficiently achieve an array of complex carbonyl compounds, including fluorinated amino acids and oligopeptides of great interest in medicinal chemistry and chemical biology. This reaction relies on a nickel-catalyzed one-pot cascade process to assemble CO, arylboronic acids, and difluoroalkyl electrophiles across the carbon-carbon double bond of alkenes, paving a new way for base-metal-catalyzed carbonylative cascade reaction.
Iridium-Catalyzed γ-Selective Hydroboration of γ-Substituted Allylic Amides
Zhao, Hongliang,Gao, Qian,Zhang, Yajuan,Zhang, Panke,Xu, Senmiao
supporting information, p. 2861 - 2866 (2020/04/02)
Reported here for the first time is the Ir-catalyzed γ-selective hydroboration of γ-substituted allylic amides under mild reaction conditions. A variety of functional groups could be compatible with reaction conditions, affording γ-branched amides in good yields with ≤97% γ-selectivity. We have also demonstrated that the obtained borylated products could be used in a series of C-O, C-F, C-Br, and C-C bond-forming reactions.
Synthetic studies towards N-substituted 3-vinyl-4-piperidineacetic acid derivatives
Johnson, David A.,Gribble, Gordon W.
, p. 178 - 195 (2019/05/15)
The synthesis and full characterization of two new (E)-2-butenyl)-5-amino-2-pentenoates, (Z)-4-[N-(3-buten-1-yl)benzamido]-2-buten-1-ol, and (Z)-1-chloro-4-[N-(3-buten-l-yl)benzamido]-2-butene are reported. These were designed as substrates for a projected thermal ene cyclization leading to the N-substituted 3-vinyl-4-piperidineacetic acid scaffold. Although conditions for this ene-cyclization have not yet been uncovered, the ease of preparation of these ene-cyclization substrates gives promise for their future use.
Photocatalytic atom transfer radical addition to olefins utilizing novel photocatalysts
Voutyritsa, Errika,Triandafillidi, Ierasia,Tzouras, Nikolaos V.,Nikitas, Nikolaos F.,Pefkianakis, Eleftherios K.,Vougioukalakis, Georgios C.,Kokotos, Christoforos G.
supporting information, (2019/05/24)
Photocatalysis is a rapidly evolving area of research in modern organic synthesis. Among the traditional photocatalysts, metal-complexes based on ruthenium or iridium are the most common. Herein, we present the synthesis of two photoactive, ruthenium-based complexes bearing pyridine-quinoline or terpyridine ligands with extended aromatic conjugation. Our complexes were utilized in the atom transfer radical addition (ATRA) of haloalkanes to olefins, using bromoacetonitrile or bromotrichloromethane as the source of the alkyl group. The tailor-made ruthenium-based catalyst bearing the pyridine-quinoline bidentate ligand proved to be the best-performing photocatalyst, among a range of metal complexes and organocatalysts, efficiently catalyzing both reactions. These photocatalytic atom transfer protocols can be expanded into a broad scope of olefins. In both protocols, the photocatalytic reactions led to products in good to excellent isolated yields.
Photocatalytic Synthesis of γ-Lactones from Alkenes: High-Resolution Mass Spectrometry as a Tool to Study Photoredox Reactions
Triandafillidi, Ierasia,Kokotou, Maroula G.,Kokotos, Christoforos G.
supporting information, p. 36 - 39 (2018/01/17)
A mild photocatalytic manifold for the synthesis of γ-lactones has been developed. Utilizing Ru(bpy)3Cl2 as the photocatalyst, a cheap and reproducible synthetic protocol for γ-lactones has been introduced. Mechanistic studies revealed the successful monitoring of photocatalytic reactions and radical intermediates via high-resolution mass spectrometry.
Fluorocyclisation via I(I)/I(III) catalysis: A concise route to fluorinated oxazolines
Daniliuc, Constantin G.,Gilmour, Ryan,Kehr, Gerald,Meyer, Stephanie,Scheidt, Felix,Thiehoff, Christian,Yilmaz, Gülay
supporting information, p. 1021 - 1027 (2020/05/06)
Herein, we describe a catalytic fluorooxygenation of readily accessible N-allylcarboxamides via an I(I)/I(III) manifold to generate 2-oxazolines containing a fluoromethyl group. Catalysis is conditional on the oxidation competence of Selectfluor, whilst HF serves as both a fluoride source and Br?nsted acid activator. The C(sp3)–F bond of the mono-fluoromethyl unit and the C(sp3)–O bond of the ring are aligned in a synclinal relationship thereby engaging in stabilising hyperconjugative interactions with vicinal, electron-rich σ-bonds (σC–C→σ*C–F and σC–H→σ*C–O). This manifestation of the stereoelectronic gauche effect was established by X-ray crystallographic analysis of a representative example. Given the importance of fluorine in drug discovery, its ability to modulate conformation, and the prevalence of the 2-oxazoline scaffold in Nature, this strategy provides a rapid entry into an important bioisostere class.
Visible-Light Photoredox Catalyzed Oxidative/Reductive Cyclization Reaction of N-Cyanamide Alkenes for the Synthesis of Sulfonated Quinazolinones
Qian, Ping,Deng, Yu,Mei, Haibo,Han, Jianlin,Zhou, Jie,Pan, Yi
supporting information, p. 4798 - 4801 (2017/09/23)
An efficient photocatalytic oxidative/reductive cyclization reaction of N-cyanamide alkenes with arylsulfinic acids or arylsulfonyl chlorides, which proceeds through C-S, C-C, and C-N bond formations, is reported. This photocatalytic reaction was carried out under mild conditions, which provides a new strategy for the synthesis of sulfonated quinazolinones. Furthermore, a one-pot procedure to achieve terminal alkenes has been explored via elimination of the obtained sulfonated quinazolinones under basic conditions.
Copper-Catalyzed Divergent Trifluoromethylation/Cyclization of Unactivated Alkenes
Zheng, Jing,Deng, Ziyang,Zhang, Yan,Cui, Sunliang
supporting information, p. 746 - 751 (2016/03/09)
Most of the precedent copper-catalyzed trifluoromethylation reactions of unactivated alkenes concern terminal alkenes, and these processes are terminated in elimination, or nucleophilic addition, or semipinacol rearrangement, or C-H bond functionalization steps. In this study, we develop a trifluoromethylation method for both unactivated terminal and internal alkenes to enable divergent late-stage radical cyclization and achieve high molecular complexity. These cyclizations are well consistent with Baldwin's rule. Furthermore, a kinetic isotope effect (KIE) study and control reactions were conducted, and a plausible mechanism is proposed.
