Best Synthetic Methods: Construction of Aromatic and Heteroaromatic Rings

Anthracene derivatives have been used for a wide range of applications and many different synthetic methods for their preparation have been developed. However, despite continued synthetic efforts, introducing substituents in some positions has remained difficult. Here we present a method for the synthesis of 2,3,6,7-substituted anthracene derivatives, one of the most challenging anthracene substitution patterns to obtain. The method is exemplified by the preparation of 2,3,6,7-anthracenetetracarbonitrile and employs a newly developed, stable protected 1,2,4,5-benzenetetracarbaldehyde as the precursor. The precursor can be obtained in two scalable synthetic steps from 2,5-dibromoterephthalaldehyde and is converted into the anthracene derivative by a double intermolecular Wittig reaction under very mild conditions followed by a deprotection and intramolecular double ring-closing condensation reaction. Further modification of the precursor is expected to enable the introduction of additional substituents in other positions and may even enable the synthesis of fully substituted anthracene derivatives by the presented approach.<br>

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Сatalytic Phosphorylation of Aromatic C-H Bonds: from Traditional Approaches to Electrochemistry

Current Organic Chemistry ◽

10.2174/1385272822666191007145336 ◽

2019 ◽

Vol 23 (16) ◽

pp. 1756-1770

Author(s):

Sofia Strekalova ◽

Mikhail Khrizanforov ◽

Oleg Sinyashin ◽

Yulia Budnikova

Keyword(s):

Organophosphorus Compounds ◽

Normal Pressure ◽

Acid Group ◽

Synthetic Methods ◽

Heteroaromatic Compounds ◽

Anti Cancer ◽

Phosphonic Acid Group ◽

Traditional Approaches ◽

Anti Hiv Agents ◽

Anti Hiv

The interest in organophosphorus compounds with a C-P bond is due to their wide use in various fields, especially in medicine and agrochemistry. Prominent examples of anti-cancer, antibacterial, and anti-HIV agents are therapeutic candidates containing a phosphonic acid group fragment. This review provides modern synthetic methods for obtaining phosphorylated aromatic and heteroaromatic compounds with the participation of complexes and salts of various metals developed in recent years as well modern protocol - electrochemical synthesis which allows carrying out reactions at room temperature and normal pressure with no additional oxidants or bases. Herein, we demonstrate new trends and evolution of phosphorylation reactions in catalysis.

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