52889-62-0Relevant articles and documents
Iron-Catalyzed Vinylzincation of Terminal Alkynes
Huang, Qiang,Su, Yu-Xuan,Sun, Wei,Hu, Meng-Yang,Wang, Wei-Na,Zhu, Shou-Fei
supporting information, p. 515 - 526 (2022/01/08)
Organozinc reagents are among the most commonly used organometallic reagents in modern synthetic chemistry, and multifunctionalized organozinc reagents can be synthesized from structurally simple, readily available ones by means of alkyne carbozincation. However, this method suffers from poor tolerance for terminal alkynes, and transformation of the newly introduced organic groups is difficult, which limits its applications. Herein, we report a method for vinylzincation of terminal alkynes catalyzed by newly developed iron catalysts bearing 1,10-phenanthroline-imine ligands. This method provides efficient access to novel organozinc reagents with a diverse array of structures and functional groups from readily available vinylzinc reagents and terminal alkynes. The method features excellent functional group tolerance (tolerated functional groups include amino, amide, cyano, ester, hydroxyl, sulfonyl, acetal, phosphono, pyridyl), a good substrate scope (suitable terminal alkynes include aryl, alkenyl, and alkyl acetylenes bearing various functional groups), and high chemoselectivity, regioselectivity, and stereoselectivity. The method could significantly improve the synthetic efficiency of various important bioactive molecules, including vitamin A. Mechanistic studies indicate that the new iron-1,10-phenanthroline-imine catalysts developed in this study have an extremely crowded reaction pocket, which promotes efficient transfer of the vinyl group to the alkynes, disfavors substitution reactions between the zinc reagent and the terminal C–H bond of the alkynes, and prevents the further reactions of the products. Our findings show that iron catalysts can be superior to other metal catalysts in terms of activity, chemoselectivity, regioselectivity, and stereoselectivity when suitable ligands are used.
Iodine-Catalyzed Methylthiolative Annulation of 2-Alkynyl Biaryls with DMSO: A Metal-Free Approach to 9-Sulfenylphenanthrenes
Chatterjee, Tanmay,Mukherjee, Nilanjana
, p. 7881 - 7890 (2021/06/28)
An iodine-catalyzed sustainable, cost-effective, and atom-economic synthetic methodology is developed to synthesize a wide variety of valuable sulfenylphenanthrenes and polycyclic heteroaromatics in moderate to high yield through electrophilic thiolative annulation of 2-alkynyl biaryls (6-endo-dig cyclization) using methyl sulfoxides such as dimethyl sulfoxide (DMSO) as the sulfur source under transition-metal-free conditions. The transformation requires only iodine in a catalytic amount and trifluoroacetic anhydride. Notably, DMSO played multiple roles such as methylthiolating reagent, oxidant, and solvent in this reaction.
Gold-Catalyzed Synthesis of π-Extended Carbazole-Based Systems and their Application as Organic Semiconductors
Hendrich, Christoph M.,Hannibal, Valentin D.,Eberle, Lukas,Hertwig, Leif E.,Zschieschang, Ute,Rominger, Frank,Rudolph, Matthias,Klauk, Hagen,K. Hashmi, A. Stephen
, p. 1401 - 1407 (2021/02/03)
Herein we describe a gold-catalyzed bidirectional synthesis of N-heteropolycyclic compounds bearing carbazole moieties – namely π-extended benzodicarbazoles and π-extended indolocarbazoles. Overall, four previously unknown core structures were synthesized. This approach is convergent, modular and the gold-catalyzed key step comprises of a cascade reaction starting from stable di-azido compounds. The obtained molecules were fully characterized and their optical and electronic properties as well as their performance in organic thin-film transistors generated by vacuum deposition were studied. Charge-carrier mobilities of up to 0.3 cm2/Vs were measured. (Figure presented.).
