1855-47-6Relevant academic research and scientific papers
An unusual, DDQ-promoted oxidative rearrangement of 9,9-disubstituted 1,4,5,8-tetrahydro-4a,8a-methanonaphthalenes
Barasz, Jonah A.,Ghaffari, Ali H.,Otte, Douglas A.,Thamattoor, Dasan M.
, p. 64 - 65 (2002)
The action of excess DDQ on 1,4,5,8-tetrahydro-4a,8a-methanonaphthalenes bearing a methyl group and one other substituent (cyclopropyl, methyl, phenyl) at the 9 position resulted in a peculiar oxidative rearrangement to 1-vinylnaphthalene derivatives. Two closely related mechanisms, both of which involve a 1,5-sigmatropic shift of the one-carbon bridge (Berson-Willcott rearrangement), are considered for this novel process.
Electrochemical fluorosulfonylation of alkenes to access vicinal fluorinated sulfones derivatives
Zhao, Bin,Pan, Zichen,Zhu, Anqiao,Yue, Yanni,Ma, Mengtao,Xue, Fei
supporting information, (2022/01/24)
Herein, we report a practical and efficient fluorosulfonylation of the various alkenes with sulfonyl radical sources (RSO2NHNH2) and Et3N·3HF as cost-effective fluorination reagents under mild conditions. Remarkably, this
1,3-Difunctionalization of β-alkyl nitroalkenes via combination of Lewis base catalysis and radical oxidation
Wang, Ye,Zheng, Lei,Shi, Xiaodong,Chen, Yunfeng
supporting information, p. 886 - 889 (2021/02/01)
Upon treatment with a Lewis base catalyst, β-alkyl-substituted nitroalkenes could be readily converted into allylic nitro compounds. Examples of either C-1 or C-3 functionalization methods have been reported through nitro-elimination, giving alkene products. In this work, successful 1,3-difunctionalization was achieved through a synergetic Lewis base catalysis and TBHP radical oxidation, giving vinylic alkoxyamines in good to excellent yields. This work further extended the general synthetic application of β-alkyl nitroalkenes.
Formal Allylation and Enantioselective Cyclopropanation of Donor/Acceptor Rhodium(II) Azavinyl Carbenes
Liu, Zhili,Chen, Lianfen,Zhu, Dong,Zhu, Shifa
supporting information, p. 1275 - 1279 (2021/02/20)
A highly efficient formal allylation of dihydronaphthotriazoles with alkenes under rhodium(II) catalysis is reported. Various allyl dihydronaphthalene derivatives were furnished via rhodium(II) azavinyl carbenes with moderate to good yields and excellent chemoselectivity. When monosubstituted alkenes are used, cyclopropanation occurs and good to excellent enantioselectivities have been achieved. Particularly noteworthy is the allylic C(sp2)-H activation instead of traditional C(sp3)-H activation in the formal allylation process.
The cascade coupling/iodoaminocyclization reaction of trifluoroacetimidoyl chlorides and allylamines: metal-free access to 2-trifluoromethyl-imidazolines
Chen, Zhengkai,Du, Shiying,Song, Yufei,Wang, Le-Cheng,Wu, Xiao-Feng
supporting information, p. 6115 - 6119 (2021/07/21)
A metal-free cascade coupling/iodoaminocyclization reaction for the rapid assembly of 2-trifluoromethyl-imidazolines has been disclosed. The transformation applies readily accessible trifluoroacetimidoyl chlorides, allylamines andN-iodosuccinimides as the starting substrates, achieving an efficient and straightforward pathway to construct diverse imidazoline derivatives. Excellent efficiency of the reaction is observed (higher than 90% isolated yield for half of the examples), and the obtained imidazoline products bearing a pendent iodomethyl group could be easily transformed into other synthetically valuable compounds.
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 N-Alkylpyridin-4-ones and Thiazolo[3,2- a]pyridin-5-ones through Pummerer-Type Reactions
Huang, Jingjia,Hu, Gang,An, Shaoyu,Chen, Dongding,Li, Minglei,Li, Pingfan
, p. 9758 - 9769 (2019/08/08)
N-Alkylated 4-pyridones were obtained through a one-pot procedure involving either normal or interrupted Pummerer reactions between triflic anhydride-activated sulfoxides and 4-fluoropyridine derivatives, followed by hydrolysis. On the other hand, triflic anhydride-activated benzyl 6-fluoro-2-pyridyl sulfoxide could react with alkenes or alkynes to afford thiazolo[3,2-a]pyridin-5-ones, via the pyridinium salt intermediates.
The Allylic Acetoxylation of 1,1-Disubstituted Alkenes Catalyzed by a Palladium(II)/Monothiadiazole Ligand System
Jin, Can,Li, Xiaohan,Sun, Bin,Wang, Jiayang,Yang, Jin,Yu, Chuangming,Zhang, Xun,Zhuang, Xiaohui
, p. 1479 - 1483 (2019/07/15)
A palladium(II)/monothiadiazole ligand catalytic system and its application in catalyzing the acetoxylation of 1,1-disubstituted alkenes have been developed. With this newly designed monothiadiazole thioether ligand, the reaction showed a broad scope with respect to 1,1-disubstituted olefins, giving the corresponding products in yields of 30-86percent.
Copper-Catalyzed Enantio- and Diastereoselective Addition of Silicon Nucleophiles to 3,3-Disubstituted Cyclopropenes
Zhang, Liangliang,Oestreich, Martin
supporting information, p. 14304 - 14307 (2019/11/13)
A highly stereocontrolled syn-addition of silicon nucleophiles across cyclopropenes with two different geminal substituents at C3 is reported. Diastereomeric ratios are excellent throughout (d.r.≥98:2) and enantiomeric excesses usually higher than 90 %, even reaching 99 %. This copper-catalyzed C?Si bond formation closes the gap of the direct synthesis of α-chiral cyclopropylsilanes.
Synthesis of 2-Substituted Propenes by Bidentate Phosphine-Assisted Methylenation of Acyl Fluorides and Acyl Chlorides with AlMe3
Wang, Xiu,Wang, Zhenhua,Asanuma, Yuya,Nishihara, Yasushi
supporting information, p. 3640 - 3643 (2019/05/17)
Bidentate phosphine-assisted methylenation of acyl fluorides and acyl chlorides with substituted with aryl, alkenyl, and alkyl groups trimethylaluminum afforded an array of 2-substituted propene derivatives. The addition of a catalytic amount of DPPM increased an efficiency of the reactions. Trimethylaluminum as the methylenation reagent not only eliminates the presynthesis of methylene transfer reagent, but provides an efficient method for the synthesis of a series of 2-substituted propenes.
