133216-88-3Relevant academic research and scientific papers
Sc(OTf)3-catalyzed [3 + 2]-cycloaddition of nitrones with ynones
He, Chun-Ting,Han, Xiao-Li,Zhang, Yan-Xue,Du, Zhen-Ting,Si, Chang-Mei,Wei, Bang-Guo
supporting information, p. 457 - 466 (2021/01/29)
An efficient approach to access functionalized (2,3-dihydroisoxazol-4-yl) ketones has been developed by reacting nitrones 4 with ynones 7 or terminal ynones 10 in a one-pot fashion. The reaction went through a formal Sc(OTf)3-catalyzed [3 + 2]-cycloaddition process to generate a number of functionalized (2,3-dihydroisoxazol-4-yl) ketones 11aa-11aw, 11ba-11la and 12aa-12ae in moderate to good yields. This journal is
Enantioselective Inverse Electron Demand (3 + 2) Cycloaddition of Palladium-Oxyallyl Enabled by a Hydrogen-Bond-Donating Ligand
Zheng, Yin,Qin, Tianzhu,Zi, Weiwei
supporting information, p. 1038 - 1045 (2021/01/25)
Cycloaddition reactions between oxyallyl cations and alkenes are important transformations for the construction of ring systems. Although (4 + 3) cycloaddition reactions of oxyallyl cations are well-developed, (3 + 2) cycloadditions remain rare, and an as
Copper(I)-catalyzed stereodivergent propargylation of N-acetyl mannosamine for protecting group minimal synthesis of C3-substituted sialic acids
Ishizawa, Kouhei,Majima, Sohei,Wei, Xiao-Feng,Mitsunuma, Harunobu,Shimizu, Yohei,Kanai, Motomu
, p. 10615 - 10628 (2019/09/30)
Copper(I)-catalyzed stereodivergent nucleophilic propargylation at the anomeric carbon of unprotected N-acetyl mannosamine was developed using 3-substituted allenylboronates as a nucleophile. The homopropargylic alcohol products contained two contiguous s
Asymmetric Propargylic Radical Cyanation Enabled by Dual Organophotoredox and Copper Catalysis
Lu, Fu-Dong,Liu, Dan,Zhu, Lei,Lu, Liang-Qiu,Yang, Qian,Zhou, Quan-Quan,Wei, Yi,Lan, Yu,Xiao, Wen-Jing
supporting information, p. 6167 - 6172 (2019/04/17)
The first asymmetric propargylic radical cyanation was realized through a dual photoredox and copper catalysis. An organic photocatalyst serves to both generate propargyl radicals and oxidize Cu(I) species to Cu(II) species. A chiral Cu complex functions as an efficient organometallic catalyst to resemble the propargyl radical and cyanide in an enantio-controlled manner. Thus, a diverse range of optically active propargyl cyanides were produced with high reaction efficiency and enantioselectivities (28 examples, 57-97% yields and 83-98% ee). Moreover, mechanistic investigations including experiments and density functional theory calculations were performed to illustrate on the reaction pathway and stereochemical results.
Gold(I)-Catalyzed Tandem Cycloisomerization and Fluorination of 1,3(4)-Enyne Esters with NFSI: One-Pot Assembly of 5-Fluoro- Cyclopentenones
Chen, Xianxiao,Zhou, Yuanyuan,Hong, Mei,Ling, Yuan,Yin, Dongliang,Wang, Shifa,Zhang, Xiaoxiang,Rao, Weidong
supporting information, p. 3700 - 3708 (2018/09/12)
An efficient synthetic approach for the synthesis of 5-fluoro-cyclopentenones containing a fluorine-substituted carbon stereocenter that relies on gold(I)-catalyzed cycloisomerization and fluorination sequence of 1,3(4)-enyne esters with N-fluorbenzensulfonimide (NFSI) is described. This tandem transformation exhibited a broad substrate scope and excellent functional group compatibility, providing a novel protocol for rapid assembly 5-fluoro-cyclopentenones in good to excellent yields under mild reaction conditions. The mechanistic studies revealed that the transformation involves a gold-catalyzed cycloisomerization and electrophilic fluorination cascade to give the 5-fluoro-cyclopentenones. (Figure presented.).
Gold-Catalyzed Dehydrogenative Cycloisomerization of 1,4-Enyne Esters to 3,5-Disubstituted Phenol Derivatives
Chen, Cuili,Chen, Xianxiao,Zhang, Xiaoxiang,Wang, Shifa,Rao, Weidong,Chan, Philip Wai Hong
supporting information, p. 4359 - 4368 (2017/12/26)
A method to prepare synthetically important 3,5-disubstituted phenol derivatives that relies on the sequential gold(I)-catalyzed dehydrogenative cycloisomerization of 1,4-enyne esters in the presence of 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) or N-fluorobenzenesulfonimide (NFSI) is described. The synthetic versatility of the methodology was exemplified by a gram-scale reaction of one example, the ease to realize subsequent functional transformations of an adduct, and the application of the method to the synthesis of the bioactive molecule LUF5771. (Figure presented.).
Copper(II)-Catalyzed [4+1] annulation of propargylamines with N,O-acetals: Entry to the synthesis of polysubstituted pyrrole derivatives
Sakai, Norio,Hori, Hiroaki,Ogiwara, Yohei
supporting information, p. 1905 - 1909 (2015/03/18)
Described herein is the CuCl2-catalyzed [4+1] annulation of a variety of propargylamines with N,O-acetals that function as a C1 unit, leading to the production of polysubstituted pyrrole derivatives. Three important features of the N,O-acetal during the [4+1] annulation series via 5-endo-dig cyclization are described: an enolizable substituent adjacent to the central sp3-carbon is required, the central sp3-carbon displays the functions of both an electrophile and a nucleophile, and liberation of the secondary amine smoothly leads to the aromatization. A CuCl2-catalyzed [4+1] annulation of propargylamines with N,O-acetals having an ester, a ketone, and an amide moiety, leading to the facile preparation of polysubstituted pyrrole derivatives is presented. This annulation series was achieved through 5-endo-dig cyclization and subsequent aromatization in one pot.
Construction of 1,5-enynes by stereospecific Pd-catalyzed allyl-propargyl cross-couplings
Ardolino, Michael J.,Morken, James P.
supporting information; scheme or table, p. 8770 - 8773 (2012/07/02)
The palladium-catalyzed cross-coupling of chiral propargyl acetates and allyl boronates delivers chiral 1,5-enynes with excellent levels of chirality transfer and can be applied across a broad range of substrates.
Iron-catalyzed unexpected easy access to stereodefined trimethylsilyl vinyl ketenes
Chai, Guobi,Fu, Chunling,Ma, Shengming
supporting information; experimental part, p. 4058 - 4061 (2012/10/08)
Stereodefined trimethylsilyl vinyl ketenes with polysubstitution have been synthesized highly regio- and stereoselectively via an iron-catalyzed reaction of 2-trimethylsilyl-2,3-allenoates with Grignard reagents in good to excellent yields. The reaction w
Palladacycle-catalyzed reaction of bicyclic alkenes with terminal ynones: Regiospecific synthesis of polysubstituted furans
Ge, Guang-Cun,Mo, Dong-Liang,Ding, Chang-Hua,Dai, Li-Xin,Hou, Xue-Long
supporting information, p. 5756 - 5759 (2013/01/15)
A new synthetic strategy to access polysubstituted furans regiospecifically has been developed using simple bicyclic alkenes and terminal ynones as starting materials with palladacycles as unique active catalysts. A rational mechanism has also been proposed. This reaction features mild reaction conditions, easily available starting materials and palladacycle catalysts, a wide substrate scope, and high regiospecificity.
