A gram-scale synthesis of a series of 1,1,n,n-tetramethyl[n](2,11)teropyrenophanes (n=7-9) has been accomplished as well as the first synthesis of the next higher homologue 1,1,10,10-tetramethyl[10](2,11)teropyrenophane. The scale-up of the original small-scale synthesis required the development of several heavily modified synthetic methods, including a chlorination/Friedel-Crafts alkylation protocol and an iodination/Wurtz coupling protocol, which were performed on 25-30 g and 30-60 g scales, respectively. Two separate sets of conditions for the key teropyrene-forming cyclodehydrogenation reaction at the end of the synthetic pathway were developed, an acid-promoted one for the two less strained congeners and an acid-free method for the two more strained homologues.
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http://dx.doi.org/10.1002/chem.202003828 | DOI Listing |
Chem Asian J
January 2025
Meiji Pharmaceutical University, Pharmaceutical Sciences, 2-522-1 Noshio, 204-8588, Kiyose, JAPAN.
The catalytic indirect reductive quenching method is facilitated by a combination of Ir(III) photoredox and sulfide dual-catalysis system. This study demonstrated a method for synthesizing multi-substituted furans by using a photoredox/sulfide dual-catalysis system. This method enables the synthesis of various furan derivatives, including spirofurans and phthalans.
View Article and Find Full Text PDFOrg Biomol Chem
January 2025
School of Chemistry and Chemical Engineering, Guangxi Colleges and Universities Key Laboratory of Applied Chemistry Technology and Resource Development, Guangxi University, Nanning 530004, Guangxi, P. R. China.
We present a mild and efficient method for the arylation of N-H heteroarenes using a low-loading Pd/keYPhos catalyst (0.8 mol%). This approach employs inexpensive and structurally diverse aryl chlorides as electrophiles in reactions with indoles, pyrroles, and carbazole, enabling the construction of a wide range of -arylated products.
View Article and Find Full Text PDFOrg Biomol Chem
January 2025
Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan.
The reductive amination of naturally abundant triglycerides is a promising approach for the synthesis of fatty amines. However, existing catalytic systems for this transformation typically require harsh reaction conditions. Herein, we present a titanium oxide-supported platinum-molybdenum (Pt-Mo/TiO) catalyst that promotes the reductive amination of triglycerides to fatty amines.
View Article and Find Full Text PDFNat Chem
January 2025
Department of Chemistry, Scripps Research, La Jolla, CA, USA.
Amino alcohols are vital in natural products, pharmaceuticals and agrochemicals, and as key building blocks for various applications. Traditional synthesis methods often rely on polar bond retrosynthetic analysis, requiring extensive protecting group manipulations that complicate direct access. Here we show a streamlined approach using a serine-derived chiral carboxylic acid in stereoselective electrocatalytic decarboxylative transformations, enabling efficient access to enantiopure amino alcohols.
View Article and Find Full Text PDFChem Asian J
January 2025
Mahidol University Faculty of Science, Chemistry, Rama VI Road, 10400, Bangkok, THAILAND.
Described herein is a facile electrochemical strategy for the generation of formaldehyde from N,N-dimethylacetamide (DMA) and water (H2O) toward a direct and site-selective N-hydroxymethylation of indoles and derivatives. Mechanistic studies suggested that N-(hydroxymethyl)-N-methylacetamide generated in situ from DMA/H2O under electrochemical conditions serves as a formaldehyde surrogate. The developed methodology features mild, base- and metal catalyst-free conditions.
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