17582-84-2Relevant articles and documents
Lactonization with concomitant 1,2-aryl migration and alkoxylation mediated by dialkoxyphenyl iodides generatedin situ
Cheng, Yifu,Du, Yunfei,He, Jiaxin,Jalil, Ayesha,Li, Guangchen,Yu, Zhenyang,Zhang, Jingran,Zhao, Kang
supporting information, p. 7426 - 7429 (2021/08/03)
A series of alkoxylated isobenzofuranones were conveniently synthesized from the reaction of 2-(1-arylvinyl)benzoic acids with PhI(OR)2, generatedin situfrom the reaction of iodosobenzene (PhIO) with alkyl alcohols. This hypervalent iodine medi
Copper-Catalyzed Enantioselective Hydroalkoxylation of Alkenols for the Synthesis of Cyclic Ethers
Chen, Dake,Berhane, Ilyas A.,Chemler, Sherry R.
supporting information, p. 7409 - 7414 (2020/06/29)
The copper-catalyzed enantioselective intramolecular hydroalkoxylation of unactivated alkenes for the synthesis of tetrahydrofurans, phthalans, isochromans, and morpholines from 4- and 5-alkenols is reported. The substrate scope is complementary to existing enantioselective alkene hydroalkoxylations and is broad with respect to substrate backbone and alkene substitution. The asymmetric induction and isotopic labeling studies support a polar/radical mechanism involving enantioselective oxycupration followed by C-[Cu] homolysis and hydrogen atom transfer. Synthesis of the antifungal insecticide furametpyr was accomplished.
Metal-Free Arylation-Lactonization Sequence of γ-Alkenoic Acids Using Anilines as Aryl Radical Precursors
Felipe-Blanco, Diego,Gonzalez-Gomez, Jose C.
, p. 7735 - 7744 (2019/12/24)
The presence of salicylic acid (10 mol-%) and H2O (10 equiv.) significantly improves the arylation-lactonization sequence of γ-alkenoic acids with in situ formed diazonium salts (from bench stable anilines). The reaction is finished in less than 5 h without thermal or photochemical activation, giving access to a variety of γ,γ-disubstituted butyrolactones. The protocol is user-friendly and can be used at gram-scale or adapted to transform alkenols into phthalanes. Control experiments revealed that aryl radicals participate in the reaction and a plausible mechanism is proposed to include this and other mechanistic investigations, for the catalyzed and the background reaction.
Copper-Catalyzed Modular Amino Oxygenation of Alkenes: Access to Diverse 1,2-Amino Oxygen-Containing Skeletons
Hemric, Brett N.,Chen, Andy W.,Wang, Qiu
supporting information, p. 1468 - 1488 (2019/01/25)
Copper-catalyzed alkene amino oxygenation reactions using O-acylhydroxylamines have been achieved for a rapid and modular access to diverse 1,2-amino oxygen-containing molecules. This transformation is applicable to the use of alcohols, carbonyls, oximes, and thio-carboxylic acids as nucleophiles on both terminal and internal alkenes. Mild reaction conditions tolerate a wide range of functional groups, including ether, ester, amide, carbamate, and halide. The reaction protocol allows for starting with free amines as the precursor of O-benzoylhydroxylamines to eliminate their isolation and purification, contributing to broader synthetic utilities. Mechanistic investigations reveal the amino oxygenation reactions may involve distinct pathways, depending on different oxygen nucleophiles.
Visible Light Photocatalytic Radical Addition/Cyclization Reaction of o-Vinyl-N-Alkoxybenzamides for Synthesis of CF3-Containing Iminoisobenzofurans
Liu, Zhi-Cheng,Zhao, Quan-Qing,Chen, Jun,Tang, Qian,Chen, Jia-Rong,Xiao, Wen-Jing
supporting information, p. 2087 - 2092 (2018/04/11)
A visible light-induced photocatalytic radical addition/cyclization reaction of o-vinyl-N-alkoxybenzamides has been accomplished for efficient synthesis of diversely functionalized CF3-containing iminoisobenzofurans. This external oxidant-free and mild protocol features ready availability of starting materials, excellent regioselectivity, good substrate scope and functional group tolerance. (Figure presented.).
Synthesis of Chiral Sulfonyl Lactones via Copper-Catalyzed Asymmetric Radical Reaction of DABCO?(SO2)
Wang, Yang,Deng, Lingling,Zhou, Jie,Wang, Xiaochen,Mei, Haibo,Han, Jianlin,Pan, Yi
supporting information, p. 1060 - 1065 (2018/01/22)
In the present work, an asymmetric copper-catalyzed radical multi-component cascade reaction of an unsaturated carboxylic acid, aryldiazonium tetrafluoroborate, and DABCO?(SO2)2 (DABSO) has been developed for the enantioselective synthesis of sulfonyl lactones. In this reaction, this SO2 surrogate, DABSO was applied for the first time in the construction of chiral compounds. This multiple-step asymmetric radical reaction was carried out under mild conditions and tolerated a wide range of substrates, resulting in the corresponding sulfonyl lactones with up to 95% chemical yields and 88% ee. The current reaction enriches the research contents of DABSO, and provides a new and efficient strategy to chiral functionalized lactones bearing quarternary stereogenic center. (Figure presented.).
Divergent Access to (1,1) and (1,2)-Azidolactones from Alkenes using Hypervalent Iodine Reagents
Alazet, Sébastien,Le Vaillant, Franck,Nicolai, Stefano,Courant, Thibaut,Waser, Jerome
supporting information, p. 9501 - 9504 (2017/07/22)
A versatile synthesis of azidolactones through azidation and cyclization of carboxylic acids onto alkenes has been developed. Based on either photoredox or palladium catalysis, (1,1) and (1,2) azido lactones can be selectively synthesized. The choice of catalyst and benziodoxol(on)e reagent serving as azide source was essential to initiate either a radical or Lewis acid mediated process with divergent outcome. These transformations were carried out under mild conditions using a low catalyst loading and gave access to a large scope of azido lactones.
Photoredox-Catalyzed Cascade Difluoroalkylation and Intramolecular Cyclization for Construction of Fluorinated γ-Butyrolactones
Sha, Wanxing,Zhang, Wenzhong,Ni, Shengyang,Mei, Haibo,Han, Jianlin,Pan, Yi
, p. 9824 - 9831 (2017/09/23)
A cascade visible-light photocatalytic difluoroalkylation and intramolecular cyclization reaction has been developed for the synthesis of difluoroalkylated oxygen heterocycles. The reaction was carried out under very mild conditions, affording fluorinated
Intramolecular Hydroamidation of ortho-Vinyl Benzamides Promoted by Potassium tert-Butoxide/N,N-Dimethylformamide
Chen, Zhen-Yu,Wu, Liang-Yu,Fang, Hai-Sheng,Zhang, Ting,Mao, Zhi-Feng,Zou, Yong,Zhang, Xue-Jing,Yan, Ming
supporting information, p. 3894 - 3899 (2017/10/07)
An intramolecular hydroamidation of ortho-vinyl benzamides had been developed. The reaction was promoted efficiently by potassium tert-butoxide and N,N-dimethylformamide without the need for strong oxidants or transition-metal catalysts. A series of dihyd
Alkene Dioxygenation with Malonoyl Peroxides: Synthesis of γ-Lactones, Isobenzofuranones, and Tetrahydrofurans
Alamillo-Ferrer, Carla,Karabourniotis-Sotti, Marianna,Kennedy, Alan R.,Campbell, Matthew,Tomkinson, Nicholas C. O.
, p. 3102 - 3105 (2016/07/13)
Treatment of homoallylic alcohols or carboxylic acids with malonoyl peroxide 1 provides a stereoselective method for the preparation of tetrahydrofurans, γ-lactones, and isobenzofuranones in 44-82% yield and up to 27:1 trans selectivity. Application of this simple and effective heterocyclization in the synthesis of the antidepressant citalopram is also described.
