Nitrogen–Iodine Exchange of Diaryliodonium Salts: Access to Acridine and Carbazole
摘要:
A nitrogen iodine exchange protocol of diaryliodonium salts with sodium azide salt is developed for general construction of significant functional acridines and carbazoles, in which introduction of nitrogen at a late stage was successfully established avoiding heteroatom incompatibility. Inorganic sodium azide served as the sole nitrogen atom source in this transformation. The diversiform functional acridines and carbazoles were comprehensively achieved through annulated diaryliodonium salts, respectively. Notably, Acridine orange (a fluorescent indicator for cell lysosomal dye) and Carprofen (a non steroidal anti-inflammatory drug) were efficiently established through this protocol.
halogen (Cl, Br, and even I), aldehyde, ketone, carboxyl, and cyano. Moreover, the photoredox catalysis with NaI and stoichiometric PPh3 provides also an alternative entry to Cadogan-type reductive amination when o-nitrobiarenes were used.
Total Synthesis of Dixiamycin B by Electrochemical Oxidation
作者:Brandon R. Rosen、Erik W. Werner、Alexander G. O’Brien、Phil S. Baran
DOI:10.1021/ja5013323
日期:2014.4.16
class of naturalproducts for which chemical synthesis has no practical solution. To meet this challenge, an electrochemicaloxidativedimerization method was developed, which was applied as the pivotal step of the first total synthesis of dixiamycin B. This method is also general for N–N dimerization of substituted carbazoles and β-carbolines, providing entry into seldom explored chemical space.
N-N-连接的二聚吲哚生物碱代表了一类未开发的天然产物,化学合成没有实际解决方案。为了应对这一挑战,开发了一种电化学氧化二聚法,该方法被用作双氧霉素 B 首次全合成的关键步骤。 该方法也适用于取代咔唑和 β-咔啉的 N-N 二聚化,提供了进入很少探索化学空间。
作者:Zhi-Chao Qi、Qin-Xin Lou、Yuan Niu、Shang-Dong Yang
DOI:10.1039/d0cc07596e
日期:——
A palladium-catalyzed, temporary P(O) directing group assisted C–H bondarylation of carbazoles was achieved. The release of the directing group occurs spontaneously in the reaction and the mechanistic studies indicate that acid is essential for N–P bondcleavage.
Recyclable copper catalyzed nitrogenation of biphenyl halides: a direct approach to carbazoles
作者:Yang Ou、Ning Jiao
DOI:10.1039/c3cc41443d
日期:——
A novel A21-CuI catalyzed direct nitrogenation of biphenyl halides for the direct synthesis of carbazoles via a direct C–H amination process has been developed. A recyclable and inexpensive Cu-catalyst was successfully employed in N-heterocyclic compound synthesis via tandem azidation and C–H amination, which makes this protocol very practical and easy to handle.
endergonic formation of the intermediate complex of nitrobiarenes and PPh3, which corresponds with experimental findings regarding reactiontemperature. The robust synthetic capacity of the photoredox Cadogan reaction systems has been demonstrated by the viable productivity of a broad range of carbazoles and related N-heterocycles with good tolerance of various functionalities.
已发现可见光驱动的光化学卡多根型环化。发现有机 DA 型光敏剂 4CzIPN 是将能量从光子转移到瞬态中间体的有效介质,该中间体打破了卡多根反应中的脱氧壁垒,并使无温和金属的咔唑和相关杂环成为可能。DFT 计算结果表明硝基双芳烃和 PPh 3的中间体复合物的温和吸能形成,这与关于反应温度的实验结果一致。光氧化还原 Cadogan 反应系统的强大合成能力已通过广泛范围的咔唑和相关N-杂环的可行生产力得到证明,这些N-杂环对各种官能团具有良好的耐受性。