412335-94-5Relevant academic research and scientific papers
Br?nsted acid-catalyzed Friedel-Crafts-type alkylation of arenes with α-aryl diazoacetates
Chen, Wenming,Chen, Guifang,Wang, Biao,Wang, Wei,Huang, Wei,Tian, Xu
supporting information, (2021/01/25)
An efficient Br?nsted acid-catalyzed Friedel-Crafts-type alkylation of arenes with α-aryl diazoacetates has been developed. This protocol enables effective access to various highly functionalized diarylmethane derivatives in moderate to high yields. Moreo
Asymmetric Intramolecular Hydroalkoxylation of Unactivated Alkenes Catalyzed by Chiral N-Triflyl Phosphoramide and TiCl4?
Cheng, Aolin,Li, Yingkun,Ma, Jiguo,Wang, Xinxu,Zhang, Yi,Zhao, Baoguo,Zhao, Guoqing,Zhao, Pengyuan
, p. 565 - 569 (2020/04/23)
By using a combination of a chiral N-triflyl phosphoramide and TiCl4 as the catalyst, a new process for asymmetric intramolecular hydroalkoxylation of unactivated alkenes was developed, producing various chiral tetrahydrofuran derivatives in 51%—99% yields with 30%—71% ee's.
Copper-Catalyzed Modular Amino Oxygenation of Alkenes: Access to Diverse 1,2-Amino Oxygen-Containing Skeletons
Hemric, Brett N.,Chen, Andy W.,Wang, Qiu
, 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.
Niobium-Catalyzed Intramolecular Addition of O-H and N-H Bonds to Alkenes: A Tool for Hydrofunctionalization
Ferrand, Laura,Tang, Yue,Aubert, Corinne,Fensterbank, Louis,Mouriès-Mansuy, Virginie,Petit, Marc,Amatore, Muriel
, p. 2062 - 2065 (2017/04/28)
A convenient, versatile, and easy to handle intramolecular hydrofunctionalization of alkenes (C-O and C-N bonds formation) is reported using a novel niobium-based catalytic system. This atom economic and eco-friendly methodology provides an additional synthetic tool for the straightforward formation of valuable building blocks enabling molecular complexity. Various pyran, furan, pyrrolidine, piperidine, lactone, and lactam derivatives as well as spirocyclic compounds are produced in high yields and selectivities.
Intramolecular Hydroalkoxylation of Unactivated Alkenes Using Silane-Iodine Catalytic System
Fujita, Shoji,Abe, Masanori,Shibuya, Masatoshi,Yamamoto, Yoshihiko
, p. 3822 - 3825 (2015/08/18)
A novel catalytic system using I2 and PhSiH3 for the intramolecular hydroalkoxylation of unactivated alkenes is described. NMR study indicated that in situ generated PhSiH2I is a possible active catalytic species. This catalytic system allows an efficient intramolecular hydroalkoxylation of phenyl-, trialkyl-, and 1,1-dialkyl-substituted alkenes as well as a variety of unactivated monoalkyl- and 1,2-dialkyl-substituted alkenes at room temperature. Mechanistic consideration based on significant experimental observations is also discussed.
Isomerization of olefins triggered by rhodium-catalyzed C-H bond activation: Control of endocyclic β-hydrogen elimination
Yip, Stephanie Y. Y.,A?ssa, Christophe
, p. 6870 - 6873 (2015/06/02)
Five-membered metallacycles are typically reluctant to undergo endocyclic β-hydrogen elimination. The rhodium-catalyzed isomerization of 4-pentenals into 3-pentenals occurs through this elementary step and cleavage of two C-H bonds, as supported by deuterium-labeling studies. The reaction proceeds without decarbonylation, leads to trans olefins exclusively, and tolerates other olefins normally prone to isomerization. Endocyclic β-hydrogen elimination can also be controlled in an enantiodivergent reaction on a racemic mixture.
Synthesis of β,β-disubstituted γ-butyrolactones by chemo-selective oxidation of 1,4-diols and γ-hydroxy olefins with rucl3/NaIO4
Gao, Rong,Fan, Rong,Canney, Daniel J.
supporting information, p. 661 - 665 (2015/03/14)
Substituted γ-butyrolactones represent an important group of structural fragments commonly found in natural products, receptor ligands, and drug molecules. Interest in preparing a library of substituted γ-butyrolactones and finding that limited routes to β-substituted lactones exist, led to the development of an efficient approach for the synthesis of β,β-disubstituted γ-butyrolactones. Readily prepared substituted 1,4-diols and γ-hydroxy olefins were treated with the -RuCl3/NaIO4 oxidation system to provide the target β,β-disubstituted γ-butyrolactones in modest to good yields. The reaction goes through a lactol intermediate that was isolated and characterized for selected compounds. The approach supplies an efficient and versatile method for the synthesis of these important heterocyclic structures. Importantly, the present work is the first report that demonstrates the ability of RuCl3/NaIO4 to selectively oxidize primary hydroxyl groups in the presence of secondary alcohols to prepare lactones in good yields.
Intramolecular hydroalkoxylation in Bronsted acidic ionic liquids and its application to the synthesis of (±)-centrolobine
Jeong, Yunkyung,Kim, Do-Young,Choi, Yunsil,Ryu, Jae-Sang
supporting information; experimental part, p. 374 - 378 (2011/02/28)
The SO3H-tethered imidazolium and triazolium salts, nonvolatile and recyclable Bronsted acidic ionic liquids, efficiently mediate intramolecular hydroalkoxylations of alkenyl alcohols. They have been successfully employed in the synthesis of (±)-centrolobine.
Multicatalytic synthesis of complex tetrahydrofurans involving bismuth(iii) triflate catalyzed intramolecular hydroalkoxylation of unactivated olefins
Kelly, Brendan D.,Allen, Julia M.,Tundel, Rachel E.,Lambert, Tristan H.
supporting information; experimental part, p. 1381 - 1383 (2009/10/02)
A multicatalytic synthesis of complex tetrahydrofurans has been developed involving a Bi(OTf)3-catalyzed nucleophilic addition/ hydroalkoxylation sequence. Complex tetrahydrofuranyl products may be formed rapidly in high yield and with good diastereoselectivity. The demonstrated scope of hydroalkoxylation has also been expanded to include substrates bearing useful functional handles including carboxylate ester, olefin, nitrile, and nitro groups.
Efficient intramolecular hydroalkoxylation/cyclization of unactivated alkenols mediated by lanthanide triflate ionic liquids
Dzudza, Alma,Marks, Tobin J.
supporting information; experimental part, p. 1523 - 1526 (2009/09/06)
Lanthanide triflates, Ln(OTf)3, serve as efficient catalysts for the intramolecular hydroalkoxylation (HO)/cyclization of primary/secondary and aliphatic/aromatic hydroxyalkenes in room temperature ionic liquids (RTlLs). Cyclizations are effective in the formation of five-and sixmembered oxygen heterocycles with Markovnikov-type selectivity. Reaction rates exhibit first-order dependence on [Ln3+] and [substrate].
