61360-99-4Relevant academic research and scientific papers
Stereoselective and Atom-Economic Alkenyl C-H Allylation/Alkenylation in Aqueous Media by Iridium Catalysis
Ding, Liyuan,Huang, Yinhua,Lu, Xiunan,Shen, Wenzhou,Xu, Liangyao,Yu, Feifei,Zhang, Jian,Zhong, Guofu,Zhong, Liangjun
, p. 7225 - 7237 (2020/07/07)
A practical and atom-economic protocol for the stereoselective preparation of various 1,4-and 1,3-diene skeletons through iridium-catalyzed directed olefinic C-H allylation and alkenylation of NH-Ts acrylamides in water was developed. This reaction tolerated a wide scope of substrates under simple reaction conditions and enabled successful gram-scale preparation. Furthermore, an asymmetric variant of this reaction giving enantioenriched 1,4-dienes was achieved employing a chiral diene-iridium complex as the catalyst.
Iridium-catalyzed alkenyl C-H allylation using conjugated dienes
Xu, Liangyao,Meng, Keke,Zhang, Jian,Sun, Yaling,Lu, Xiunan,Li, Tingyan,Jiang, Yan,Zhong, Guofu
supporting information, p. 9757 - 9760 (2019/08/20)
An iridium-catalyzed C-H allylation of acrylamides with conjugated dienes was developed, using NH-Ts amide as the directing group. The ligand- and additive-free protocol provided a convenient and atom economic synthesis of branched 1,4-diene skeletons, enabling the tolerance of a wide scope of functionalities such as OMe, F, Cl, Br and CF3. The utility of this protocol is also demonstrated by a preparative scale, as well as C-H functionalization of artemisic amide. Furthermore, NH-Ts amide was efficiently removed by methylation and hydrolysis procedures to provide 1,4-dienoic acid.
Rhodium-Catalyzed Defluorinative Vinylation of gem-Difluoroalkenes for the Synthesis of 2-Fluoro-1,3-dienes
Song, Shengjin,Liu, Huan,Wang, Lu,Zhu, Chuan,Loh, Teck-Peng,Feng, Chao
supporting information, p. 1036 - 1040 (2019/09/16)
Herein, we present a strategy for the formation of 2-fluoro-1,3-diene derivatives via rhodium-catalyzed direct C(sp2)—C(sp2) cross-coupling of gem-difluoroalkenes and acrylamides. By merging Rh(III)-catalyzed C(sp2)–H bond activation and nucleophilic addition/F-elimination of gem-difluoroalkene, an efficient defluorinative vinylation reaction is uncovered, which leads to the generation of 2-fluoro-1,3-dienes in moderate to good yields with excellent stereoselectivity under mild conditions. Preliminary mechanistic study suggests unique effects of fluorine substituents which allow the reactivity profile not observed with the congeners bearing heavier halides.
Switchable C-H Functionalization of N-Tosyl Acrylamides with Acryloylsilanes
Song, Shengjin,Lu, Ping,Liu, Huan,Cai, Sai-Hu,Feng, Chao,Loh, Teck-Peng
supporting information, p. 2869 - 2872 (2017/06/13)
A controllable Rh-catalyzed protocol to access alkylation and alkenylation-annulation of N-tosyl acrylamide with acryloyl silane is reported. In contrast to the directing group or catalyst-dependent divergent sp2 C-H alkylation/alkenylation, the intrinsic property of acryloylsilane allows the switchable reaction manifold, thereby affording either alkylation or annulation products with slight modification of the reaction conditions.
Rhodium(iii)-catalyzed C-H allylation of electron-deficient alkenes with allyl acetates
Feng, Chao,Feng, Daming,Loh, Teck-Peng
supporting information, p. 342 - 345 (2015/01/09)
Rhodium-catalyzed C-H allylation of acrylamides with allyl acetates is reported. The use of weakly coordinating directing group resulted in high reaction efficiency, broad functionality tolerance and excellent γ-selectivity, which opens a new synthetic pathway for the access of 1,4-diene skeletons.
Catalytic dicyanative 5-exo- And 6-endo-cyclization triggered by cyanopalladation of alkynes
Arai, Shigeru,Koike, Yuka,Nishida, Atsushi
experimental part, p. 893 - 900 (2010/07/06)
A stereoselective dicyanative 5-exo- and 6endo-cyclization using various enynes has been investigated. The mode of cyclization is critically controlled by the structure of the substrates. For example, N-allyl derivatives prefer 5-exo-cyclization, while methacryloyl amides are transformed to the corresponding lactams with tetra substituted carbons at the alpha-position via 6-endo-cyclization. Both reactions include syn-cyanopalladation to carbon≡carbon triple bonds in the initial step, and sequential cyclization followed by reductive elimination in one operation enables the construction of the highly functionalized nitrogen heterocycles. The scope of suitable substrates and a proposed mechanism are also described.
