Intramolecular carbonyl-ene reactions in the synthesis of peri-oxygenated hydroaromatics
作者:Shyam Basak、Dipakranjan Mal
DOI:10.1016/j.tet.2016.02.033
日期:2016.4
Suzuki coupling of 2-formylphenylboronic acids, are shown to provide cycloalkylidene ene products under acidic conditions. Susceptibility of the products to aromatization is manoeuvred by varying the reaction conditions and catalysts including binol-derived Brønsted acid catalysts. A peri-effect is identified as a controlling factor for the aromatizations. Several oxidative transformations of an ene product
A convenient synthesis of multisubstituted azatriphenylenes is reported. [Ir(cod)Cl]2/diphosphine is an efficient catalyst for the [2 + 2 + 2] cycloaddition of biaryl-linked diynes with nitriles to give multisubstituted azatriphenylenes in high yields. Aromatic, heteroaromatic, aliphatic, and functionalized nitriles could be used for the reaction.
Chemoselective Cross-Coupling between Two Different and Unactivated C(aryl)–O Bonds Enabled by Chromium Catalysis
作者:Jinghua Tang、Liu Leo Liu、Shangru Yang、Xuefeng Cong、Meiming Luo、Xiaoming Zeng
DOI:10.1021/jacs.0c00283
日期:2020.4.29
combination of low-cost Cr(II) salt, 4,4-di-tert-butyl-2,2-dipyridyl (dtbpy) ligand and magnesium reductant shows high reactivity in promoting the reductive cross-coupling of aryl methyl ether derivatives with aryl esters, by cleavage and coupling of two different C(aryl)-O bonds undermildconditions. The formation of active low-valent Cr species by reduction of CrCl2 with Mg can be considered, which prefers
A novel Cu(0)-Cu(I)-mediated Caryl-Caryl Ullmann coupling has been successfully developed. The use of Cu(I) salts allowed the reactions to proceed under relatively mild conditions (65 °C in DMSO for 15–72 h). The developed method was compatible with a relatively wide range of functional groups simultaneously present on the aromatic ring of different electronic nature. The aryl halides with an electron-withdrawing
A Synthetic Strategy for the Construction of Functionalized Triphenylene Frameworks via Palladium Catalyzed Intramolecular Annulation/Decyanogenative C–H Bond Alkenylation
作者:Sachin S. Ichake、Bharath Kumar Villuri、Sabbasani Rajasekhara Reddy、Veerababurao Kavala、Ching-Fa Yao
DOI:10.1021/acs.orglett.9b00532
日期:2019.4.5
The palladium catalyzed synthesis of 14-phenylbenzo[f]tetraphene-9-carbonitrile derivatives as core polycyclicaromatic hydrocarbons (PAHs) was achieved via an intramolecular annulation and decyanogenative C–H bond alkenylation strategy. A readily synthesized Knoevenagel condensation product of [1,1′-biphenyl]-2,2′-dicarbaldehyde with benzyl cyanide converted successfully into 14-phenylbenzo[f]tet
钯催化的14-苯基苯并[ f ]四苯基-9-腈衍生物作为核心多环芳烃(PAHs)的合成是通过分子内环化和脱氰C–H键烯基化策略实现的。一种易于合成的[1,1'-联苯] -2,2'-二甲醛与苄基氰的Knoevenagel缩合产物成功地成功转化为14-苯基苯并[ f ]四苯基-9-腈衍生物,收率高达94%。转化涉及分子内级联CC键的形成以及CH键的裂解序列。