N-containing heteroaromatics are important substructures found in numerous natural or synthetic alkaloids. The diversity of the structures encountered, as well as their biological and pharmaceutical relevance, have motivated research aimed at the development of new economical, efficient and selective synthetic strategies to access these compounds. Over more than 100 years of research, this hot topic has resulted in numerous so-called "classical synthetic methods" that have really contributed to this important area. However, when the selective synthesis of highly functional heteroaromatics like indoles, quinolones, indoxyls, etc. is considered these methods remain limited. Recently transition metal-catalysed (TM-catalysed) procedures for the synthesis of such compounds and further transformations, have been developed providing increased tolerance toward functional groups and leading generally to higher reaction yields. Many of these methods have proven to be the most powerful and are currently applied in target- or diversity-oriented syntheses. This review article aims at reporting the recent developments devoted to this important area, focusing on the use of heterogeneous catalysed procedures that include either the formation of the heterocyclic ring towards the nuclei or their transformations to highly substituted compounds.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6264783 | PMC |
http://dx.doi.org/10.3390/molecules16065241 | DOI Listing |
J Org Chem
November 2022
Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
The amino group in aminocarboxylic acids is sufficiently basic to be protonated in strong acids, and consequently, ionization of the carboxylic acid to an acylium ion is blocked due to charge-charge repulsion. Thus, acylation of aromatic compounds is significantly retarded in Friedel-Craft type reactions. We found that Friedel-Crafts acylation with aminocarboxylic acids can proceed smoothly even in a strong Brønsted acid (triflic acid, TfOH) if the Lewis base PO is added.
View Article and Find Full Text PDFACS Appl Mater Interfaces
October 2022
Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR 999077, China.
In organic resistive random-access memory (ReRAM) devices, deeply understanding how to control the performance of π-conjugated semiconductors through molecular-shape-engineering is important and highly desirable. Herein, we design a family of N-containing heteroaromatic semiconductors with molecular shapes moving from mono-branched 1Q to di-branched 2Q and tri-branched 3Q. We find that this molecular-shape engineering can induce reliable binary to ternary ReRAM switching, affording a highly enhanced device yield that satisfies the practical requirement.
View Article and Find Full Text PDFJ Am Chem Soc
February 2022
Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Science, Chinese Academy of Science, 345 Lingling Lu, Shanghai 200032, China.
-CF compounds constitute valuable targets in medicinal chemistry. Extensive studies have been reported for the preparation of -CF compounds through fluorination and trifluoromethylation of N-containing compounds. The development of new synthetic methods from abundant and easily available substrates is highly desirable but still challenging.
View Article and Find Full Text PDFOrg Lett
February 2021
Institute of Medicine and Materials Applied Technologies, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong 273165, P. R. China.
The construction of functional N-containing active biomolecules and bidentate nitrogen ligands by electroreductive pyridylation of N-heteroaromatics is an eye-catching task and challenge. A simple and practical electroreductive-induced C3 pyridylation of quinoxalin-2(1)-ones with readily available cyanopyridines is reported. More than 36 examples are supplied, and the reaction performed in >95% yield.
View Article and Find Full Text PDFOrg Biomol Chem
June 2019
Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan.
A variety of N-containing heteroarenes were site-selectively introduced at the C31-position of a chlorophyll-a derivative possessing a 3-vinyl group through a C-N+ bond via oxidative reactions using iodine in the presence of a silver(i) salt. Electron-rich N-heteroarenes were effectively substituted, while electron-withdrawing or bulky nitrogen-neighboring substituents suppressed the reactivities. The cationic products formed were characterized by 1D/2D NMR, and their optical properties were also investigated.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!