6335-34-8Relevant articles and documents
Acridine Orange Hemi(Zinc Chloride) Salt as a Lewis Acid-Photoredox Hybrid Catalyst for the Generation of α-Carbonyl Radicals
Das, Sanju,Mandal, Tanumoy,De Sarkar, Suman
supporting information, p. 755 - 765 (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.
Visible-Light-Driven Aryl Migration and Cyclization of α-Azido Amides
Liang, Siyu,Wei, Kaijie,Lin, Yajun,Liu, Tuming,Wei, Dian,Han, Bing,Yu, Wei
supporting information, p. 4527 - 4531 (2021/06/28)
This paper reports two new visible-light-promoted radical reactions of α-azido amides. By catalysis of [Ir(ppy)2(dtbbpy)]PF6 with i-Pr2NEt as the reducing agent, N-aryl α-azido tertiary amides were first converted to the corresponding aminyl radicals through reduction of the azido group; the aminyl radicals then underwent N-to-N aryl migration to give α-anilinyl-functionalized amides. α-Azido secondary amides, on the other hand, reacted with the solvent ethanol and i-Pr2NEt to afford the imidazolinone products.
Synthesis of Oxindole Derivatives via Intramolecular C–H Insertion of Diazoamides Using Ru(II)-Pheox Catalyst
Phan Thi Thanh, Nga,Dang Thi Thu, Huong,Tone, Masaya,Inoue, Hayato,Iwasa, Seiji
, (2020/10/02)
This work presented the efficient intramolecular aromatic C–H insertion of diazoacetamide. The 1a–1o diazo compounds (except for 1k) were converted into their corresponding oxindoles via an intramolecular C–H insertion reaction in the presence of a Ru catalyst. The Ru-Pheox catalyst was shown to be highly efficient in this transformation in terms of the regioselectivity, producing the desired products in excellent yield (99%). The efficiency of the Ru catalyst reached 580 (TON) and 156 min?1 (TOF).