SmI 2 -mediated synthesis of 2,4-diarylpyrroles from phenacyl azides
摘要:
A novel reduction of phenacyl azides induced by SmI2 was investigated and 2,4-diarylpyrroles were prepared in moderate to good yields under mild conditions. (C) 2001 Elsevier Science Ltd. All rights reserved.
我们报告了在双相中性相转移条件下使用叠氮化钠对羰基化合物进行氧化或脱羧氧化α-叠氮化的高性能I + / H 2 O 2催化。为了诱导更高的反应活性,尤其是对于1,3-二羰基化合物的α-叠氮化,我们设计了结构紧凑的异吲哚啉衍生的带有吸电子基团的季碘化铵催化剂。I + / H 2 O 2的非生产性分解途径催化量可以通过使用催化量的自由基捕获剂来抑制。这种氧化偶合耐受各种官能团,可以很容易地应用于结构多样的复杂分子的后期α-叠氮化。此外,我们实现了1,3-二羰基化合物的对映选择性α-叠氮化,这是手性次碘酸盐催化剂与对映选择性分子间氧化偶联的第一个成功实例。
Pb(OAc)4(CH3)3SiN3 reacts with simple nucleophilic olefins to form mostly diazides and azide-acetoxy compounds,2 while with steroidal olefines α-azidosteroidketones3 are afforded. Contrary to this result the title reagent reacts not only with nucleophilic but also with electrophilic double-bounds yielding α-azido-carbonyl compounds. Not any azide-acetoxy compound is formed. Compound 14 indicates that
The Synthesis of α-Azidoesters and Geminal Triazides
作者:Philipp Klahn、Hellmuth Erhardt、Andreas Kotthaus、Stefan F. Kirsch
DOI:10.1002/anie.201402433
日期:2014.7.21
representatives of this novel class of triazide compounds: Despite their high nitrogen content, the geminaltriazides are easy to handle, even when preparative‐scale syntheses are performed. (Caution: These procedures still require protective measures!) The triazides are now broadly available for further studies regarding their properties and reactivity. Furthermore, we show how the method can be used to
Concurrent Formation of N–H Imines and Carbonyl Compounds by Ruthenium-Catalyzed C–C Bond Cleavage of β-Hydroxy Azides
作者:Jeong Min Lee、Dae Young Bae、Jin Yong Park、Hwi Yul Jo、Eunsung Lee、Young Ho Rhee、Jaiwook Park
DOI:10.1021/acs.orglett.0c01145
日期:2020.6.19
A commercial cyclopentadienylrutenium dicarbonyl dimer ([CpRu(CO)2]2) efficiently catalyzes the formation of N–H imines and carbonyl compounds simultaneously from β-hydroxy azides via C–Cbond cleavage under visible light. Density functional theory calculations for the cleavage reaction support the mechanism involving chelation of alkoxy azide species and liberation of nitrogen as the driving force
vinyl arenes with trimethylsilylazide and molecular oxygen as stoichiometric oxidant was achieved. In contrast to photocatalysts based on iridium, ruthenium, or organic dyes, [Cu(dap)2]Cl or [Cu(dap)Cl2] were found to be unique for this transformation, which is attributed to their ability to interact with the substrates through ligand exchange and rebound mechanisms. CuII is proposed as the catalytically
用三甲基甲硅烷基叠氮化物和分子氧作为化学计量氧化剂实现了乙烯基芳烃的可见光加速氧化叠氮化。与基于铱,钌或有机染料的光催化剂相反,发现[Cu(dap)2 ] Cl或[Cu(dap)Cl 2 ]对于这种转化是独特的,这归因于它们与金属,金属或金属的相互作用。底物通过配体交换和反弹机制。有人建议将铜II作为催化活性物质,将其与叠氮化物配位后将进行光加速均质分解,从而形成铜I和叠氮化物自由基。这种激活原则(CU II -X→铜我+ X 。)开启了铜基光催化的新途径。