121746-04-1Relevant articles and documents
Applications of Consecutive Radical Addition-Elimination Reactions in Synthesis
Baldwin, Jack E.,Kelly, David R.
, p. 682 - 684 (1985)
Alkyl radicals add to the tri-n-butylstannyl substituted terminus of several alkenes; elimination of the stannyl radical results in a preparatively useful, carbon-carbon bond forming reaction, under mild and neutral conditions.
Dehydrative Synthesis of Functionalized Skipped Dienes from Stabilized Phosphonium Ylides and Allylic Alcohols in Water
Ma, Xiantao,Yu, Jing,Han, Cuijie,Zhou, Qiuju,Ren, Mengjuan,Li, Lixin,Tang, Lin
, p. 1023 - 1027 (2019)
A mild and extra activator-free dehydrative alkylation of stabilized phosphonium ylides with allylic alcohols in water is developed in the presence of [Pd(allyl)Cl]2/dppf catalyst. A wide range of aryl, heteroaryl, alkyl and even allylic tertiary alcohols can readily react with stabilized phosphonium ylides with high regioselectivity for the efficient synthesis of functionalized skipped dienes in moderate to high yields. The role of water was investigated by means of a high-resolution mass spectrum and diffusion-ordered spectroscopy nuclear magnetic resonance, and the results revealed that water might play a crucial role in the formation of the π-allylpalladium complex via hydrogen bond. However, the present method is not suitable for water-sensitive phosphonium ylides. (Figure presented.).
A new approach to the synthesis of ethyl (4E)-alkenoates
Shakhmaev,Sunagatullina,Zorin
, p. 2018 - 2020 (2013)
A new approach to the preparation of ethyl (4E)-alkenoates was developed on the basis of Fe-catalyzed cross-coupling of ethyl (4E)-5-chloropent-4-enoate with the Grignard reagents. The starting ethyl (4E)-5-chloropent-4-enoate was obtained by alkylation of malonic ester of (E)-1,3-dichloropropene followed by decarbethoxylation.
Lewis Base Catalyzed, Sulfenium Ion Initiated Enantioselective, Spiroketalization Cascade
Denmark, Scott E.,Hilby, Kimberly M.
, p. 14250 - 14289 (2021/11/12)
A Lewis base catalyzed, enantioselective sulfenocyclization of alkenes to afford [6,6]spiroketals has been developed. The method uses a chiral Lewis base catalyst with an electrophilic sulfur source to generate enantioenriched thiiranium ion with alkenes. Upon formation, the thiiranium ion is subsequently captured in a cascade-type reaction, wherein a ketone oxygen serves as the nucleophile to open the thiiranium ion and an alcohol provides the secondary cyclization to form biorelevant spiroketals. A variety of electron-rich and electron-neutral E-substituted styrenes form the desired spiroketals in good yields with excellent enantio- and diastereoselectivities. Alkyl-substituted and terminal alkenes participate in the cascade reaction, but with a limited scope compared to the styrenyl substrates. This method allows for rapid formation of highly substituted spiroketals in good yield and excellent enantioselectivity.
Stereodivergent Nucleophilic Additions to Racemic β-Oxo Acid Derivatives: Fast Addition Outcompetes Stereoconvergence in the Archetypal Configurationally Unstable Electrophile
Crawford, Evan T.,De Jesús Cruz, Pedro,Johnson, Jeffrey S.,Liu, Shubin
supporting information, p. 16264 - 16273 (2021/10/21)
Additions of carbon nucleophiles to racemic α-stereogenic β-oxo acid derivatives that deliver enantiomerically enriched tertiary alcohols are valuable, but uncommon. This article describes stereodivergent Cu-catalyzed borylative cyclizations of racemic β-oxo acid derivatives bearing tethered pro-nucleophilic olefins to deliver highly functionalized cyclopentanols containing four contiguous stereogenic centers. The reported protocol is applicable to a range of β-oxo acid derivatives, and the diastereomeric products are readily isolable by typical chromatographic techniques. α-Stereogenic-β-keto esters are typically thought to have extreme or spontaneous configurational fragility, but mechanistic studies for this system reveal an unusual scenario wherein productive catalysis occurs on the same time scale as background substrate racemization and completely outcompetes on-cycle epimerization, even under the basic conditions of the reaction.
Synthesis of Antitricyclic Morpholine Derivatives through Iodine(III)-Mediated Intramolecular Umpolung Cycloaddition of Olefins
Deng, Qingfu,Feng, Yangyang,Xiong, Ruimei,Xiong, Yan,Yang, Chenglin,Zhang, Xiaohui
supporting information, p. 4500 - 4506 (2020/04/09)
A (diacetoxyiodo)benzene-mediated intramolecular cycloaddition of olefins to construct tricyclic morpholines is presented. A series of substituted tricyclic morpholines were obtained in one-step simple operation under mild conditions, and the NMR studies
