89619-10-3Relevant academic research and scientific papers
Absence of Intermediates in the BINOL-Derived Mg(II)/Phosphate-Catalyzed Desymmetrizative Ring Expansion of 1-Vinylcyclobutanols
Capel, Estefania,Rodríguez-Rodríguez, Marta,Uria, Uxue,Pedron, Manuel,Tejero, Tomas,Vicario, Jose L.,Merino, Pedro
supporting information, p. 693 - 707 (2022/01/04)
The catalyzed desymmetrizative ring expansion of alkenylcyclobutanols promoted by halofunctionalization of the alkene moiety with N-bromosuccinimide has been experimentally and computationally studied. The reaction yields highly enantioenriched cyclopenta
Catalytic Asymmetric Halogenation/Semipinacol Rearrangement of 3-Hydroxyl-3-vinyl Oxindoles: A Stereodivergent Kinetic Resolution Process
Cao, Weidi,Dai, Li,Feng, Xiaoming,Hu, Xinyue,Liu, Wen,Zeng, Zi,Zhou, Yuqiao
supporting information, p. 26599 - 26603 (2021/11/16)
A highly enantioselective halogenation/semipinacol rearrangement of isatin-derived allylic alcohols has been developed with a chiral N,N′-dioxide/ScIII complex as catalyst. This strategy involved a pivotal stereodivergent kinetic resolution process and provided a facile and efficient entry to optically active halo-substituted quinolone derivatives and quinoline alkaloids with a quaternary stereocenter simultaneously under mild reaction conditions. Based on the control experiments together with kinetic studies and DFT calculations, a possible catalytic cycle was proposed to illustrate the reaction process and enantiocontrol.
The intramolecular reaction of acetophenoneN-tosylhydrazone and vinyl: Br?nsted acid-promoted cationic cyclization toward polysubstituted indenes
Wang, Zhixin,Li, Yang,Chen, Fan,Qian, Peng-Cheng,Cheng, Jiang
supporting information, p. 1810 - 1813 (2021/02/27)
In the presence of TsNHNH2, a Br?nsted acid-promoted intramolecular cyclization ofo-(1-arylvinyl) acetophenone derivatives was developed, leading to polysubstituted indenes with complexity and diversity in moderate to excellent yields. In sharp contrast with either the radical or carbene involved cyclization of aldehydicN-tosylhydrazone with vinyl, a cationic cyclization pathway was involved, whereN-tosylhydrazone served as an electrophile and alkylation reagent during this transformation.
Synthesis of Unsymmetrical 1,4-Dicarbonyl Compounds by Photocatalytic Oxidative Radical Additions
Dong, Ya,Li, Ruining,Zhou, Junliang,Sun, Zhankui
supporting information, p. 6387 - 6390 (2021/08/23)
Herein we report a photocatalytic oxidative radical addition reaction for the synthesis of unsymmetrical 1,4-dicarbonyl compounds. This reaction utilizes a desulfurization process to generate electrophilic radicals, which add to α-halogenated alkenes and undergo further oxidation to deliver 1,4-dicarbonyl compounds. This mild and highly efficient method provides a valuable alternative to known strategies.
Electrochemical Semipinacol Rearrangements of Allylic Alcohols: Construction of All-Carbon Quaternary Stereocenters
Kang, Jun-Chen,Tu, Yong-Qiang,Dong, Jia-Wei,Chen, Chao,Zhou, Jia,Ding, Tong-Mei,Zai, Jian-Tao,Chen, Zhi-Min,Zhang, Shu-Yu
supporting information, p. 2536 - 2540 (2019/04/30)
The first examples of electrochemical trifluoromethylation and sulfonylation/semipinacol rearrangements of allylic alcohols were developed using cheap and stable RSO2Na (R = CF3, Ph) as reagents. Various β-trifluoromethyl and sulfonated ketones were obtained in moderate to excellent yields. This strategy provides a facile, direct, and complementary approach to construct all-carbon quaternary stereocenters. In addition, the reaction has the advantages of being chemical oxidant-free and metal-free and has safe and mild reaction conditions.
Selective Aerobic Oxygenation of Tertiary Allylic Alcohols with Molecular Oxygen
Zhu, Bencong,Shen, Tao,Huang, Xiaoqiang,Zhu, Yuchao,Song, Song,Jiao, Ning
supporting information, p. 11028 - 11032 (2019/07/08)
Aerobic epoxidation of tertiary allylic alcohols remains a significant challenge. Reported here is an efficient and highly chemoselective copper-catalyzed epoxidation and semipinacol rearrangement reaction of tertiary allylic alcohols with molecular oxygen. The solvent 1,4-dioxane activates dioxygen, thereby precluding the addition of a sacrificial reductant.
Why is cis/trans stereoinversion with Li+(THF)4 migration across the phenyl ring of α-lithiostyrene accelerated by two ortho-methyl groups?
Knorr, Rudolf,Lattke, Ernst,Ruhdorfer, Jakob,Ferchland, Kathrin,von Roman, Ulrich
, p. 1621 - 1631 (2018/02/28)
Common wisdom might anticipate that two methyl groups placed on a molecular migration route should act as an impediment. However, the “conducted tour” migration of Li+(THF)4 across the aryl ring (“π-route”) during the cis/trans stereoinversion of α-arylvinyllithiums had been found to occur with practically equal velocities in the presence of either one or two ortho-alkyl substituents. We now report that the omission of both ortho-methyl groups retards the stereoinversion process. In order to arrive at an answer to the title question, we investigate the aggregation equilibria and microsolvation states of ortho, ortho′-unsubstituted α-lithiostyrenes by means of approved secondary NMR criteria. Beyond such necessary knowledge about the ground-state properties, we provide kinetic evidence showing that the retarded cis/trans stereoinversion of α-lithiostyrene proceeds by the pseudomonomolecular, ionic mechanism with Li+(THF)4 migration.
Electrophilic Trifluoromethylthiolation/Semipinacol Rearrangement: Preparation of β-SCF3 Carbonyl Compounds with α-Quaternary Carbon Center
Xi, Chao-Chao,Chen, Zhi-Min,Zhang, Shu-Yu,Tu, Yong-Qiang
supporting information, p. 4227 - 4230 (2018/07/29)
A new and modular electrophilic trifluoromethylthiolation/semipinacol rearrangement of allylic silyl ethers has been developed under mild conditions. This approach allows the formation of a number of β-SCF3 carbonyl compounds with a cyclic and all-carbon quaternary center framework in moderate to good yields. It should be noted that this achievement is a metal-free process and just requires the use of simple acetyl chloride as an acidic promoter. Additionally, an interesting H-migration in competition with aryl-migration process was revealed.
Cyclic Hypervalent Iodine Reagents for Azidation: Safer Reagents and Photoredox-Catalyzed Ring Expansion
Alazet, Sebastien,Preindl, Johannes,Simonet-Davin, Raphael,Nicolai, Stefano,Nanchen, Annik,Meyer, Thierry,Waser, Jerome
supporting information, p. 12334 - 12356 (2018/09/27)
Azides are building blocks of increasing importance in synthetic chemistry, chemical biology, and materials science. Azidobenziodoxolone (ABX, Zhdankin reagent) is a valuable azide source, but its safety profile has not been thoroughly established. Herein, we report a safety study of ABX, which shows its hazardous nature. We introduce two derivatives, tBu-ABX and ABZ (azidobenziodazolone), with a better safety profile, and use them in established photoredox- and metal-mediated azidations, and in a new ring-expansion of silylated cyclobutanols to give azidated cyclopentanones.
Intermolecular Carboamination of Unactivated Alkenes
Zhang, Yu,Liu, Haidong,Tang, Luning,Tang, Hai-Jun,Wang, Lu,Zhu, Chuan,Feng, Chao
, p. 10695 - 10699 (2018/09/06)
Herein, we report the first example of group transfer radical addition of O-vinylhydroxylamine derivatives onto unactivated alkenes. By utilizing O-vinylhydroxylamine derivatives as both the N- and C-donors, this reaction enables intermolecular carboamination of unactivated alkenes in an atom economical fashion. As the process is initiated through N-radical addition followed by C-transfer, linear carboamination products are afforded. This differs from canonical radical carbofunctionalization of olefins, which typically favors branched product owing to initiation by C-radical addition.
