6-Aroylated Phenanthridines via Base Promoted Homolytic Aromatic Substitution (BHAS)
作者:Dirk Leifert、Constantin Gabriel Daniliuc、Armido Studer
DOI:10.1021/ol403147v
日期:2013.12.20
2-isocyanobiphenyls react with aromatic aldehydes via base promoted homolytic aromatic substitution (BHAS) to give 6-aroylated phenanthridines. Reactions occur via addition of acylradicals to the isonitrile functionality and subsequent intramolecular BHAS of the intermediate imidoyl radicals. Initiation of the radicalchainreaction is best achieved with small amounts of FeCl3 (0.4 mol %), and the commercially
Ag(i)-catalyzed oxidative decarboxylative gem-difluoromethylenation of difluoroacetates with isonitriles has been developed for the formation of C–CF2 bonds.
Where HAS you been? A manganese‐mediated annulation of 2‐isocyanobiaryls with organoboronic acids is developed for the synthesis of a broad range of phenanthridinederivatives (see scheme). Mechanistic studies indicate that the reaction proceeds by the intramolecular homolytic aromatic substitution (HAS) of an imidoyl radical intermediate.
Photochemical Synthesis of Succinic Ester-Containing Phenanthridines from Diazo Compounds as 1,4-Dicarbonyl Precursors
作者:Hai-Bing Ye、Xu-Yu Zhou、Lei Li、Xiang-Kui He、Jun Xuan
DOI:10.1021/acs.orglett.2c02313
日期:2022.8.19
We disclosed herein a straightforward photochemical method for the construction of phenanthridines containing a synthetically useful succinate unit. The reaction occurred under visible-light irradiation with cheap eosin Y Na as photoredox catalyst and a diazo compound as the succinate precursor. Under the optimal reaction conditions, a wide range of phenanthridines were obtained in moderate to good
我们在此公开了一种直接的光化学方法,用于构建含有合成有用的琥珀酸单元的菲啶。该反应在可见光照射下发生,廉价的曙红 Y Na 作为光氧化还原催化剂,重氮化合物作为琥珀酸盐前体。在最佳反应条件下,以中等至良好的收率获得了范围广泛的菲啶。请注意,最终杂环中的琥珀酸单元可以很容易地转化为许多有价值的结构,例如 γ-丁内酯、二氢呋喃-2(3 H )-酮和四氢呋喃。进行了机械实验以支持所提出的机制。
Divergent Construction of Heterocycles by SOMOphilic Isocyanide Insertion under N-Heterocyclic Carbene Catalysis
作者:Qianrong Li、Cong-Ying Zhou、Chengming Wang
DOI:10.1021/acs.orglett.2c03148
日期:2022.10.21
substitution-type radical cyclization in the absence of any light, transition metals, and external oxidants. The aldehyde-free, scalable, and operationally simple protocol tolerates diverse functionalized biaryl isonitriles and activated α-halides. Moreover, it can be further applied to the divergent construction of other N-heterocycles. Preliminary mechanistic studies disclose that an NHC-derived radical cation