7117-17-1Relevant academic research and scientific papers
Ir(iii)-Catalysed electrooxidative intramolecular dehydrogenative C-H/N-H coupling for the synthesis of N-H indoles
Chang, Sukbok,Kim, Dongwook,Kim, Youyoung
supporting information, p. 12309 - 12312 (2021/12/07)
Herein, an iridium(iii)-catalysed electrooxidative intramolecular dehydrogenative C-H/N-H coupling of unprotected 2-alkenyl anilines is described. The developed method allows the synthesis of a variety of 3-substituted N-H indole scaffolds under undivided electrolytic conditions. Mechanistic studies suggest that the reaction proceeds through the electro-oxidation induced reductive elimination pathway.
Nickel/Photo-Cocatalyzed Asymmetric Acyl-Carbamoylation of Alkenes
Fan, Pei,Lan, Yun,Zhang, Chang,Wang, Chuan
, p. 2180 - 2186 (2020/03/03)
An unprecedented asymmetric acyl-carbamoylation of pendant alkenes tethered on aryl carbamic chlorides with both aliphatic and aromatic aldehydes has been developed via the cooperative catalysis of a chiral nickel-PHOX complex and tetrabutylammonium decatungstate. This reaction represents the first example of merging hydrogen-atom-transfer photochemistry and asymmetric transition metal catalysis in difunctionalization of alkenes. Using this protocol, a variety of oxindoles bearing a challenging quaternary stereogenic center are furnished under mild conditions in highly enantioselective manner.
Chemoselectivity for Alkene Cleavage by Palladium-Catalyzed Intramolecular Diazo Group Transfer from Azide to Alkene
Frost, Grant B.,Mittelstaedt, Michaela N.,Douglas, Christopher J.
, p. 1727 - 1732 (2019/01/09)
Alkenes can be cleaved by means of the (3+2) cycloaddition and subsequent cycloreversion of 1,3-dipoles, classically ozone (O3), but the azide (R?N3) variant is rare. Chemoselectivity for these azide to alkene diazo group transfers (DGT) is typically disfavored, thus limiting their synthetic utility. Herein, this work discloses a palladium-catalyzed intramolecular azide to alkene DGT, which grants chemoselectivity over competing aziridination. The data support a catalytic cycloreversion mechanism distinct from other known metal-catalyzed azide/alkene reactions: nitrenoid/metalloradical and (3+2) cycloadditions. Kinetics experiments reveal an unusual mechanistic profile in which the catalyst is not operative during the rate-controlling step, rather, it is active during the product-determining step. Catalytic DGT was used to synthesize N-heterocyclic quinazolinones, a medicinally relevant structural core. We also report on the competing aziridination and subsequent ring expansion to another N-heterocyclic core structure of interest, benzodiazepinones.
Enantioselective Intramolecular Copper-Catalyzed Borylacylation
Whyte, Andrew,Burton, Katherine I.,Zhang, Jingli,Lautens, Mark
supporting information, p. 13927 - 13930 (2018/10/02)
An enantioselective copper-catalyzed intramolecular borylacylation is reported. The reaction proceeds through an initial enantioselective borylcupration of the styrene, followed by a nucleophilic attack on the tethered carbamoyl chloride. The products, chiral borylated 3,3-disubstituted oxindoles, were generated in excellent yields and enantioselectivities. The versatile carbon–boron bond provides a platform for a wide array of diversification.
Catalytic C-CN activation and asymmetric cyanoamidation of alkenes: Total syntheses of (+)-horsfiline, (-)-coerulescine, and (-)-esermethole
Reddy, Venkata Jaganmohan,Douglas, Christopher J.
scheme or table, p. 4719 - 4729 (2010/08/06)
The detailed study of Pd-catalyzed asymmetric cyanoamidation is reported. Excellent enantioselectivities are attributed to a chiral phosphosphoramidite ligand synthesized in one step from the commercially available materials. Cyanoamidation substrates are easy to prepare from the corresponding anilines. The 3,3-disubstituted oxindole products bear all-carbon quaternary stereocenters and contain a nitrile and an amide, which are valuable functional handles for the synthesis of many indole-containing natural products. Cyanoamidation tolerates free N-H groups, as demonstrated by the successful use of cyanoamidation in the syntheses of (+)-horsfiline and (-)-coerulescine.
Synthesis of 3,3-disubstituted oxindoles through Pd-catalyzed intramolecular cyanoamidation
Yasui, Yoshizumi,Kamisaki, Haruhi,Ishida, Takayuki,Takemoto, Yoshiji
supporting information; experimental part, p. 1980 - 1989 (2010/04/24)
The cyanoamidation of olefins was achieved. When N-(2-vinylphenyl)cyanoformamides were treated with palladium catalyst, intramolecular cyanoamidation took place to give corresponding 3,3-disubstituted oxindoles. P(t-Bu)3 showed a remarkable eff
Alkaloid synthesis via the intramolecular imidate methylide 1,3-dipolar cycloaddition reaction
Smith, Richard,Livinghouse, Tom
, p. 3559 - 3568 (2007/10/02)
A concise synthesis for the neurotoxic physostigmine alkaloid d,l-eserethole is described which relys upon an intramolecular cycloaddition reaction involving a "non-stabilized" imidate methylide and an unactivated alkene. The facility of this cyclization
