5676-32-4Relevant academic research and scientific papers
Palladium-Catalyzed Markovnikov Hydroaminocarbonylation of 1,1-Disubstituted and 1,1,2-Trisubstituted Alkenes for Formation of Amides with Quaternary Carbon
Yang, Hui-Yi,Yao, Ya-Hong,Chen, Ming,Ren, Zhi-Hui,Guan, Zheng-Hui
supporting information, p. 7298 - 7305 (2021/05/26)
Hydroaminocarbonylation of alkenes is one of the most promising yet challenging methods for the synthesis of amides. Herein, we reported the development of a novel and effective Pd-catalyzed Markovnikov hydroaminocarbonylation of 1,1-disubstituted or 1,1,2-trisubstituted alkenes with aniline hydrochloride salts to afford amides bearing an α quaternary carbon. The reaction makes use of readily available starting materials, tolerates a wide range of functional groups, and provides a facile and straightforward approach to a diverse array of amides bearing an α quaternary carbon. Mechanistic investigations suggested that the reaction proceeded through a palladium hydride pathway. The hydropalladation and CO insertion are reversible, and the aminolysis is probably the rate-limiting step.
Electrochemical fluorosulfonylation of styrenes
Jiang, Yi-Min,Yu, Yi,Wu, Shao-Fen,Yan, Hong,Yuan, Yaofeng,Ye, Ke-Yin
supporting information, p. 11481 - 11484 (2021/11/16)
An environmentally friendly and efficient electrochemical fluorosulfonylation of styrenes has been developed. With the use of sulfonylhydrazides and triethylamine trihydrofluoride, a diverse array of β-fluorosulfones could be readily obtained. This reaction features mild conditions and a broad substrate scope, which could also be conveniently extended to a gram-scale preparation.
Electrochemistry enabled selective vicinal fluorosulfenylation and fluorosulfoxidation of alkenes
Jiang, Yimin,Shi, Zhaojiang,Wu, Jinnan,Wu, Shaofen,Ye, Keyin,Yu, Yi,Yuan, Yaofeng
supporting information, (2021/11/17)
Both sulfur and fluorine play important roles in organic synthesis, the life science, and materials science. The direct incorporation of these elements into organic scaffolds with precise control of the oxidation states of sulfur moieties is of great significance. Herein, we report the highly selective electrochemical vicinal fluorosulfenylation and fluorosulfoxidation reactions of alkenes, which were enabled by the unique ability of electrochemistry to dial in the potentials on demand. Preliminary mechanistic investigations revealed that the fluorosulfenylation reaction proceeded through a radical-polar crossover mechanism involving a key episulfonium ion intermediate. Subsequent electrochemical oxidation of fluorosulfides to fluorosulfoxides were readily achieved under a higher applied potential with the adventitious H2O in the reaction mixture.
Cobalt(II)-Catalyzed Stereoselective Olefin Isomerization: Facile Access to Acyclic Trisubstituted Alkenes
Zhang, Sheng,Bedi, Deepika,Cheng, Lu,Unruh, Daniel K.,Li, Guigen,Findlater, Michael
supporting information, p. 8910 - 8917 (2020/12/23)
Stereoselective synthesis of trisubstituted alkenes is a long-standing challenge in organic chemistry, due to the small energy differences between E and Z isomers of trisubstituted alkenes (compared with 1,2-disubstituted alkenes). Transition metal-catalyzed isomerization of 1,1-disubstituted alkenes can serve as an alternative approach to trisubstituted alkenes, but it remains underdeveloped owing to issues relating to reaction efficiency and stereoselectivity. Here we show that a novel cobalt catalyst can overcome these challenges to provide an efficient and stereoselective access to a broad range of trisubstituted alkenes. This protocol is compatible with both mono- and dienes and exhibits a good functional group tolerance and scalability. Moreover, it has proven to be a useful tool to construct organic luminophores and a deuterated trisubstituted alkene. A preliminary study of the mechanism suggests that a cobalt-hydride pathway is involved in the reaction. The high stereoselectivity of the reaction is attributed to both a π-πstacking effect and the steric hindrance between substrate and catalyst.
Aqueous ZnCl2 Complex Catalyzed Prins Reaction of Silyl Glyoxylates: Access to Functionalized Tertiary α-Silyl Alcohols
Han, Man-Yi,Pan, Hong,Li, Pinhua,Wang, Lei
, p. 5825 - 5837 (2020/05/22)
An efficient Prins reaction of silyl glyoxylates in the presence of an aqueous ZnCl2 complex as a catalyst was developed, providing functionalized tertiary α-silyl alcohols in high yields under mild conditions. A preliminary investigation indicated that the aqueous ZnCl2 complex acted as a dual functional catalyst of Br?nsted and Lewis acid to activate the carbonyl groups of silyl glyoxylates via a dual-activation model.
Synthesis of Tertiary Benzylic Nitriles via Nickel-Catalyzed Markovnikov Hydrocyanation of α-Substituted Styrenes
Xing, Yidan,Yu, Rongrong,Fang, Xianjie
supporting information, p. 1008 - 1012 (2020/02/04)
The Markovnikov hydrocyanation of α-substituted styrenes enables the synthesis of tertiary benzylic nitriles under nickel catalysis. The Lewis-acid-free transformation features an unprecedented functional groups tolerance, including the-OH and-NH2 groups. A broad range of tertiary benzylic nitriles were obtained in good to excellent yields. In addition, an asymmetric version of this reaction was preliminarily investigated.
Contra-Thermodynamic, Photocatalytic E→Z Isomerization of Styrenyl Boron Species: Vectors to Facilitate Exploration of Two-Dimensional Chemical Space
Molloy, John J.,Metternich, Jan B.,Daniliuc, Constantin G.,Watson, Allan J. B.,Gilmour, Ryan
supporting information, p. 3168 - 3172 (2018/02/26)
Designing strategies to access stereodefined olefinic organoboron species is an important synthetic challenge. Despite significant advances, there is a striking paucity of routes to Z-α-substituted styrenyl organoborons. Herein, this strategic imbalance is redressed by exploiting the polarity of the C(sp2)?B bond to activate the neighboring π system, thus enabling a mild, traceless photocatalytic isomerization of readily accessible E-α-substituted styrenyl BPins to generate the corresponding Z-isomers with high fidelity. Preliminary validation of this contra-thermodynamic E→Z isomerization is demonstrated in a series of stereoretentive transformations to generate Z-configured trisubstituted alkenes, as well as in a concise synthesis of the anti-tumor agent Combretastatin A4.
Electrochemical oxidative radical oxysulfuration of styrene derivatives with thiols and nucleophilic oxygen sources
Wang, Yang,Deng, Lingling,Mei, Haibo,Du, Bingnan,Han, Jianlin,Pan, Yi
supporting information, p. 3444 - 3449 (2018/08/06)
Oxydifunctionalization of olefins represents a powerful tool and yet poses a challenging task. Previous methods have usually required a stoichiometric amount of a strong oxidant and an expensive transition-metal catalyst. This work describes the first example of the electrochemical oxysulfuration reaction of olefins with thiols and nucleophilic oxygen sources. This electrochemical difunctionalization reaction is conducted under catalyst- and oxidant-free conditions, and shows good substrate generality, affording thio-substituted alcohols, ethers and γ-lactones in good chemical yields and with excellent regioselectivities. This work represents a new and green strategy for the difunctionalization of olefins, and also provides a complementary and highly valuable prospect for current methodologies for the synthesis of thio-substituted compounds.
CATALYSTS AND METHODS FOR FORMING ALKENYL AND ALKYL SUBSTITUTED ARENES
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Paragraph 0155, (2018/03/25)
Embodiments of the present disclosure provide for Rh(I) catalysts, methods of making alkenyl substituted arenes (e.g., allyl arene, vinyl arene, and the like), methods of making alkyl substituted arenes, and the like.
Visible light-promoted dihydroxylation of styrenes with water and dioxygen
Yang, Bo,Lu, Zhan
supporting information, p. 12634 - 12637 (2017/12/02)
An efficient visible light promoted metal-free dihydroxylation of styrenes with water and dioxygen has been developed for the construction of vicinal alcohols. The protocol was operationally simple with a broad substrate scope. The mechanistic studies demonstrated that one of the hydroxyl groups came from water and the other one came from molecular oxygen. Additionally, the β-alkyoxy alcohols could also be obtained using a similar strategy.
