N,N'-bis(bromobenzyl) and N,N'-bis(halopyridinyl) derivatives of diaza-12-crown-4, diaza-15-crown-5 and diaza-18-crown-6 ethers were synthesized in high yields. The Pd-catalyzed macrocyclization reactions of these compounds were carried out using a variety of polyamines and oxadiamines were carried out to give novel macrobicyclic and macrotricyclic compounds of the cryptand type. The dependence of the yields of macropolycycles on the nature of the starting diazacrown derivatives and polyamines was established. Generally N,N'-bis(3-bromobenzyl)-substituted diazacrown ethers and oxadiamines provided better yields of the target products. The highest yield of the macrobicyclic products reached 57%.
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http://dx.doi.org/10.3390/molecules19010940 | DOI Listing |
Chempluschem
December 2024
Department of Chemical and Environmental Process Engineering, Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, Műegyetem rkp. 3., H-1111, Budapest, Hungary.
The palladium-catalyzed aminocarbonylation is one of the most effective methods for the synthesis of carboxamides having great importance. Replacing fossil-based organic solvents in this routinely used catalytic protocol with biomass-derived media is crucial for developing environmentally safe alternatives and towards sustainability considerations. In this study, the open-chain derivatives of bio-originated substance γ-valerolactone i.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
State Key Laboratory of Organometallic Chemistry and Shanghai-Hong Kong Joint Laboratory in Chemical Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, CAS 345 Lingling Road, Shanghai 200032, P. R. China.
Here, we report a novel strategy for the preparation of diverse heterocycles via a Pd-catalyzed migratory 1,1-cycloannulation reaction (MCAR) of alkenes. Starting from readily available alkenyl amines and alkenyl alcohols, this approach allows the formation of a wide range of five- to seven-membered azaheterocycles and oxaheterocycles with high efficiency and good functional group tolerance. The key to the realization of this reaction is the use of 4-iodophenol or 2-iodophenol derivatives where the phenolic hydroxyl group plays a critical role in controlling the direction of migration and the ring-size of the heterocycles through the formation of a quinone methide intermediate.
View Article and Find Full Text PDFFerrocenyl amines as directing groups for C-H activation have limitations as they are prone to undergo oxidation, allylic deamination, and β-hydride elimination. The fundamental challenge observed here is the competition between the desired C-H activation the vulnerable β-C-H bond activation of amines and fine-tuning of a suitable oxidant which avoids the oxidation of the β-C-H bond and ferrocene. Herein, the potential of an axially chiral NOBINAc ligand is revealed to implement the enantioselective Pd-catalyzed C-H activation process of ferrocenyl amines.
View Article and Find Full Text PDFJ Org Chem
January 2025
School of Chemistry and Chemical Engineering, Linyi University, The middle of Shuangling Road, Linyi, Shandong 276000, People's Republic of China.
Two novel Pd-catalyzed protocols for the controllable synthesis of benzo[]furo[2,3-]azepines and furo[3,2-]indoles have been developed by intermolecular oxidative annulation of 2-(furan-2-yl)anilines and propargyl carbonates versus intramolecular C-H amination reactions. These two protocols feature great scalability, functional group tolerance, and relatively mild reaction conditions. Notably, the robust methodologies could also provide valuable opportunities for assembling azepine-fused benzothiophene, indole-fused benzothiophene, and indole-fused benzimidazole, which may have potential applications in the synthesis of related pharmaceuticals or polymeric materials.
View Article and Find Full Text PDFOrg Biomol Chem
January 2025
State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350116, China.
This study describes the synthesis and potential applications of pentaaryl-substituted pyrroles. We report a Pd-catalyzed approach for their preparation from 4,5-diyne-9-fluorenone (1,7-diyne) and aromatic amines. The target nitrogen-doped corannulenes () were investigated computationally to understand their electronic properties.
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