7632-57-7Relevant articles and documents
Gem-Difluorination of Methylenecyclopropanes (MCPs) Featuring a Wagner-Meerwein Rearrangement: Synthesis of 2-Arylsubstituted gem-Difluorocyclobutanes
Lin, Peng-Peng,Huang, Long-Ling,Feng, Si-Xin,Yang, Shuang,Wang, Honggen,Huang, Zhi-Shu,Li, Qingjiang
supporting information, p. 3088 - 3093 (2021/05/05)
The geminal difluorocyclobutane core is a valuable structural element in medicinal chemistry. Strategies for gem-difluorocyclobutanes, especially the 2-substituted cases, are limiting and often suffer from harsh reaction conditions. Reported herein is a m
Activation and Functionalization of C-C σ Bonds of Alkylidene Cyclopropanes at Main Group Centers
Crimmin, Mark R.,Kong, Richard Y.
supporting information, p. 11967 - 11971 (2020/08/06)
Aluminum(I) and magnesium(I) compounds are reported for the C-C σ-bond activation of strained alkylidene cyclopropanes. These reactions result in the formal addition of the C-C σ bond to the main group center either at a single site (Al) or across a metal-metal bond (Mg-Mg). Mechanistic studies suggest that rather than occurring by a concerted oxidative addition, these reactions involve stepwise processes in which substrate binding to the main group metal acts as a precursor to α- or β-alkyl migration steps that break the C-C σ bond. This mechanistic understanding is used to develop the magnesium-catalyzed hydrosilylation of the C-C σ bonds of alkylidene cyclopropanes.
Ring opening of methylenecyclopropanes with halides in liquid sulfur dioxide
Le?kovskis, Kristaps,Gulbe, Krista,Mishnev, Anatoly,Turks, Māris
supporting information, (2020/10/19)
Methylenecyclopropanes (MCP) undergo ring opening reactions with group I and II metal halides and ammonium halides in liquid SO2 to afford homoallylic halides, which are versatile reagents in organic synthesis. The developed reaction conditions are compatible with acid-labile substrates such as N-Boc-protected compounds. Liquid SO2 is a polar reaction medium with Lewis acid properties that solubilizes inorganic salts. The unique properties of SO2 were demonstrated by control experiments: 1) upon performing the reactions with the aforementioned salts in conventional solvents, the MCP ring opening was not observed either in the presence of catalytic amounts of H3PO4 (similar pKa to that of H2SO3), or in the absence of H3PO4; 2) a solution of SO2 in THF exhibited similar properties to that of liquid SO2.
Strain-Promoted Oxidation of Methylenecyclopropane Derivatives using N-Hydroxyphthalimide and Molecular Oxygen in the Dark
Anderson, T. E.,Woerpel, K. A.
supporting information, (2020/07/30)
The hydroperoxidation of alkylidenecyclopropanes and other strained alkenes using an N-hydroxylamine and molecular oxygen occurred in the absence of catalyst, initiator, or light. The oxidation reaction proceeds through a radical pathway that is initiated by autoxidation of the alkene substrate. The hydroperoxides were converted to their corresponding alcohols and ketones under mild conditions.
Highly Enantioselective Construction of Strained Spiro[2,3]hexanes through a Michael Addition/Ring Expansion/Cyclization Cascade
Zhao, Chuan-Gang,Feng, Zhi-Tao,Xu, Guo-Qiang,Gao, Ang,Chen, Jing-Wei,Wang, Zhu-Yin,Xu, Peng-Fei
supporting information, p. 3058 - 3062 (2020/02/05)
We herein report a general organocatalytic enantioselective strategy for the construction of highly strained spiro[2,3]hexane skeletons from methylenecyclopropanes and a broad selection of α,β-unsaturated aldehydes. The reaction proceeds through a Michael addition followed by ring expansion of methylenecyclopropanes and nucleophilic attack of an enamine to realize the construction of spiro[2,3]hexanes. Key to the success of this approach are the utilization of an electron-deficient difluoro-substituted secondary amine catalyst and the intrinsic reactivity of methylenecyclopropanes.
Rhodium-Catalyzed Ring-Opening Hydroacylation of Alkylidenecyclopropanes with Chelating Aldehydes for the Synthesis of γ,δ-Unsaturated Ketones
Li, Hong-Shuang,Lu, Shi-Chao,Chang, Zhi-Xin,Hao, Liqiang,Li, Fu-Rong,Xia, Chengcai
supporting information, p. 5145 - 5150 (2020/07/04)
The first intermolecular ring-opening hydroacylation of alkylidenecyclopropanes with chelating aldehydes through a rhodium-catalyzed acrylamide-promoted protocol is reported. This highly efficient catalytic system enables the direct synthesis of a diverse
Synergistic combination of visible-light photo-catalytic electron and energy transfer facilitating multicomponent synthesis of β-functionalized α,α-diarylethylamines
Wu, Yanan,Zhang, Yipin,Jiang, Mingjie,Dong, Xunqing,Jalani, Hitesh B.,Li, Guigen,Lu, Hongjian
supporting information, p. 6405 - 6408 (2019/06/07)
A synthetic strategy with the visible-light photo-catalytic synergistic combination of electron and energy transfer processes has been developed. The mild reaction conditions allow the radical-radical cross-coupling phenomenon for the multicomponent synthesis of β-arylsulfonyl(diarylphosphinoyl)-α,α-diarylethyl-amines from readily available arylsulfinic acids (diarylphosphine oxides), 1,1-diarylethylenes and arylazides.
Transition Metal-Free Difunctionalization of C?C Bond with Sodium Sulfinates and Water Leading to (E)-1-Phenyl-4-sulfonylbut-1-enes
Wang, Qiao-Lin,Chen, Zan,Zhou, Quan,Zhou, Cong-Shan,Xiong, Bi-Quan,Zhang, Pan-Liang,Yang, Chang-An,Liu, Yu,Tang, Ke-Wen
supporting information, p. 2315 - 2320 (2019/04/13)
Without using any transitionmetal and base, an eco-friendly, practical and economical protocol has been established for the one-pot synthesis of diverse (E)-1-phenyl-4-sulfonylbut-1-enes from easily accessible starting materials. This strategy features a wide substrate scope, tolerates a broad range of functional groups, employs a less expensive oxidant, is operationally simple, and can be easily scaled-up. (Figure presented.).
Visible-Light-Catalyzed C-C Bond Difunctionalization of Methylenecyclopropanes with Sulfonyl Chlorides for the Synthesis of 3-Sulfonyl-1,2-dihydronaphthalenes
Liu, Yu,Wang, Qiao-Lin,Chen, Zan,Zhou, Quan,Li, Hua,Zhou, Cong-Shan,Xiong, Bi-Quan,Zhang, Pan-Liang,Tang, Ke-Wen
, p. 2829 - 2839 (2019/03/07)
A novel visible-light-catalyzed sulfonylation/arylation of carbon-carbon σ-bond with sulfonyl chlorides for the synthesis of 3-sulfonylated 1,2-dihydronaphthalenes is developed. This difunctionalization proceeds via a sequence of C=C bond sulfonylation, C-C σ-bond cleavage, and intramolecular cyclization, and the experiment result shows that the C-C σ-bond difunctionalization reaction includes a radical process. This strategy provides a simple and convenient route for difunctionalization of C-C bonds with an aromatic carbon and a sulfonyl radical by one-pot construction of a C-S bond and a new C-C bond.
Olefin-Migrative Cleavage of Cyclopropane Rings through the Nickel-Catalyzed Hydrocyanation of Allenes and Alkenes
Hori, Hiroto,Arai, Shigeru,Nishida, Atsushi
supporting information, p. 1170 - 1176 (2017/04/13)
A nickel-catalyzed hydrocyanation triggered by hydronickelation of the carbon-carbon double bonds of allenes followed by cyclopropane cleavage is described. The observed regio- and stereochemistries in the products are strongly influenced by the initial hydronickelation step, and allenyl- and methylenecyclopropanes reacted smoothly to promote the cleavage of cyclopropane. In contrast, this cleavage was not observed with vinylidenecyclopropanes, because the initial hydronickelation does not give a suitable intermediate for cleavage of the cyclopropanes. (Figure presented.).
