2918-73-2Relevant articles and documents
Bromo Radical-Mediated Photoredox Aldehyde Decarbonylation towards Transition-Metal-Free Hydroalkylation of Acrylamides at Room Temperature
Sun, Zhaozhao,Huang, Huawen,Wang, Qiaolin,Deng, Guo-Jun
supporting information, p. 453 - 458 (2021/12/03)
Herein, we report a visible-light-mediated hydroalkylation reaction of alkenes using easily available aldehydes as alkyl sources via bromo radical-promoted photoredox decarbonylation. This protocol provides an alternative entry to C(sp3)?C(sp3) bond formation and features considerable advantages including mild and clean reaction conditions, obviation for transition-metal catalyst, and good functional group compatibility.
Acridine Orange Hemi(Zinc Chloride) Salt as a Lewis Acid-Photoredox Hybrid Catalyst for the Generation of α-Carbonyl Radicals
Das, Sanju,De Sarkar, Suman,Mandal, Tanumoy
supporting information, (2021/12/10)
A readily accessible organic-inorganic hybrid catalyst is reported for the reductive fragmentation of α-halocarbonyl compounds. The robust hybrid catalyst is a self-stabilizing combination of ZnCl2 Lewis acid and acridine orange as the photoactive organic dye. Mechanistic specifics of this hybrid catalyst have been studied in detail using both photophysical and electrochemical experiments. A systematic study enabled the discovery of the appropriate Lewis acid for the effective LUMO stabilization of α-halocarbonyl compounds and thereby lowering of reduction potential within the range of a standard organic dye. This strategy resolves the issues like dehalogenative hydrogenation or homo-coupling of alkyl radicals by guiding the photoredox cycle through an oxidative quenching pathway. The cooperativity between the photoactive organic dye and the Lewis acid counterparts empowers functionalization with a wide range of coupling partners through efficient and controlled generation of alkyl radicals and serves as an appropriate alternative to the expensive late transition metal-based photocatalysts. To demonstrate the application potential of this cooperative catalytic system, four different synthetic transformations of α-carbonyl bromides were explored with broad substrate scopes.
Regioselective Acetoxylation of Terminal Olefins Using a Palladium(II)–Thiadiazole Catalyst
Li, Xiaohan,Sun, Bin,Zhou, Jiadi,Jin, Can,Yu, Chuangming
supporting information, p. 2635 - 2638 (2019/04/04)
First-time use of a palladium(II)–thiadiazole catalyst in the allylic oxidation of terminal olefins to linear allylic acetates. Employing this strategy, a range of allylic esters (20 examples) were synthesized in 43 % to 80 % yield with excellent regio- and stereoselectivities.