甲硅烷氧基芳烃在各种镍催化的偶联过程中被证明是一类通用的底物。使用Ti(O- i -Pr)4将芳基甲硅烷基醚的C(sp 2)-O键直接转变为CH-H或C-Si键或三烷基硅烷作为试剂,使用具有N-杂环卡宾(NHC)配体的镍催化剂。这些方法与甲硅烷基保护基团的有用特性相结合,使受保护的羟基直接参与高价值的键形成步骤,而不需要常规方法所需的脱保护活化策略。甲硅烷基氧芳烃的这些过程提供了与广泛使用的酚衍生物(例如新戊酸芳基酯,氨基甲酸酯和甲基醚)互补的反应性,因此能够在不保护基团和不活化基团的情况下,对复杂的底物进行化学选择性衍生化提供强大的策略。
Tandem CH activation/arylation between unactivated arenes and aryl halides catalyzed by iron complexes that bear redox‐active non‐innocent bisiminopyridine ligands is reported. Similar reactions catalyzed by first‐row transition metals have been shown to involve substrate‐based aryl radicals, whereas our catalytic system likely involves ligand‐centered radicals. Preliminary mechanistic investigations
Herein, we report a cross-electrophile coupling of benzonitrile derivatives and aryl halides with a simple cobalt-based catalytic system under mild conditions to form biaryl compounds. Even though the cobalt catalyst is able to activate the C(sp2)–CN bond alone, the use of the AlMe3 Lewis acid enhances the reactivity of benzonitriles and improves the cross-selectivity with barely any influence on the
The SuFEx‐based polycondensation between bisalkylsulfonyl fluorides (AA monomers) and bisphenol bis(t‐butyldimethylsilyl) ethers (BB monomers) using [Ph3P=N−PPh3]+[HF2]− as the catalyst is described. The AA monomers were prepared via the highly reliable Michael addition of ethenesulfonyl fluoride and amines/anilines while the BB monomers were obtained from silylation of bisphenols by t‐butyldimethylsilyl
Synthesis and Structure Confirmation of Selagibenzophenone C
作者:Dominik Kunák、Miguel Mateus、Lukas Rycek
DOI:10.1002/ejoc.202200014
日期:2022.3.22
Plants from the genus Selaginella are a source of natural products with diverse structural motifs. In this wok, the first synthesis of diarylbenzophenone selagibenzophenone C, recently isolated from Selaginella tamariscina, is reported.
卷柏属植物是具有多种结构图案的天然产物的来源。在此锅中,报道了最近从柽柳卷柏中分离得到的二芳基二苯甲酮卷柏二苯甲酮 C 的首次合成。