We report a cesium bicarbonate-mediated alkylation of 2,4-dihydroxybenzyaldehyde and 2,4-dihydroxyacetophenone to generate 4-alkylated products in acetonitrile at 80 °C with excellent regioselectivity, up to 95% isolated yields, and broad substrate scope.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9053733 | PMC |
| http://dx.doi.org/10.1016/j.tetlet.2022.153755 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Direct organocatalytic chemoselective synthesis of pharmaceutically active benzothiazole/benzoxazole-triazoles.
Org Biomol Chem
January 2025
Catalysis Laboratory, School of Chemistry, University of Hyderabad, Hyderabad-500 046, India.
Benzothiazole and benzoxazole heterocyclic ring-containing 1,4,5-trisubstituted-1,2,3-triazoles are well known for their wide range of applications in pharmaceutical and medicinal chemistry, but their high-yielding metal-free selective synthesis has always remained challenging as no comprehensive simple protocol has been outlined to date. Owing to their structural and medicinal importance, herein, we synthesized various benzothiazole and benzoxazole heterocyclic ring-containing 1,4,5-trisubstituted-1,2,3-triazoles in high to excellent yields with chemo-/regioselectivity from the library of benzothiazole/benzoxazole-ketones and aryl/alkyl-azides through an enolate-mediated organocatalytic azide-ketone [3 + 2]-cycloaddition under ambient conditions in a few hours. The commercial availability or quick synthesis of the starting materials and catalysts, a diverse substrate scope, chemo-/regioselectivity, quick synthesis of pharmaceutically active known compounds and their analogues, and numerous medicinal applications of functionalized benzothiazole/benzoxazole-triazoles are the key attractions of this metal-free organo-click reaction.
View Article and Find Full Text PDFPalladium-catalysed asymmetric cascade transformations of 4-alken-2-ynyl carbonates to construct complex frameworks.
Chem Sci
December 2024
Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University Chengdu 610041 China +86 28 85502609.
As a class of readily available and multifunctional building blocks, the chemistry of 4-alken-2-ynyl carbonates remains to be explored. Presented herein is a palladium-catalysed cascade transformative reaction between 4-alken-2-ynyl carbonates and -functionalised activated alkenes. Achiral 1,1-bisalkyl-4-alken-2-ynyl carbonates undergo highly regioselective propargylic substitution with -hydroxyphenyl-tethered activated alkenes, and an auto-tandem vinylogous addition, unusual central-carbon Tsuji-Trost alkylation, protonation and β-H elimination process is followed to furnish fused and spirocyclic frameworks with high structural complexity.
View Article and Find Full Text PDFCobalt-Catalyzed Hydroglycosylation of Alkynes for the Synthesis of Vinyl α-C-Glycosides.
Angew Chem Int Ed Engl
January 2025
Sichuan University, State Key Laboratory of Biotherapy, CHINA.
Herein we report a cobalt-catalyzed hydroglycosylation of terminal alkynes, employing bench-stable ortho-iodobiphenyl (oIB) substituted sulfides as glycosyl donors. This reaction occurs with high stereo- and regioselectivity to afford E-configured vinyl α-C-glycosides, a class of compounds nontrivial to access by previous methods. The use of a bis(oxazoline) ligand with bulky side chains is critical for the high selectivities observed.
View Article and Find Full Text PDFGold(I)-Catalyzed Nucleophilic Propargylation of Azinium Ions via Hydroxydihydroazine Intermediates.
Chemistry
January 2025
The GlaxoSmithKline Carbon Neutral Laboratories for Sustainable Chemistry, University of Nottingham, Jubilee Campus, Triumph Road, Nottingham, NG7 2TU, UK.
The nucleophilic propargylation of azinium ions with a propargylboronate proceeds efficiently under gold(I) catalysis. A range of N-alkylated pyridinium, quinolinium, and pyrazinium ions undergo propargylation with good yields and high regioselectivities to give various functionalized 1,4-dihydropyridines, 1,2-dihydropyridines, 1,4-dihydroquinolines, 1,2-dihydroquinolines, and 4,5-dihydropyrazines. No allenylation side-products are observed.
View Article and Find Full Text PDFAsymmetric Heck Silylation of Unactivated Alkenes.
Angew Chem Int Ed Engl
January 2025
Department of Chemistry, Zhejiang University, Hangzhou, 310058, China.
Heck silylation of unactivated alkenes is an efficient strategy for the synthesis of useful organosilicon compounds. However, extensive efforts have been dedicated to only achieving achiral molecules. Herein, a highly regio- and enantioselective cobalt-catalyzed Heck silylation of unactivated alkenes with hydrosilanes is reported for the first time, providing access to axially chiral alkenes in good to excellent yields with 87-98 % ee.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!