Synthesis and absolute configuration of cordiaquinone K, antifungal and larvicidal meroterpenoid isolated from the Panamanian plant, Cordia curassavica
摘要:
Total synthesis of cordiaquinone K, a new antifungal and larvicidal meroterpenoid, is reported. The absolute configuration of cordiaquinone K was confirmed by the synthesis. (C) 2003 Elsevier Ltd. All rights reserved.
Reactions of Donor-Acceptor Cyclopropanes with Naphthoquinones: Redox and Lewis Acid Catalysis Working in Concert
作者:Alexander Lücht、Lukas J. Patalag、André U. Augustin、Peter G. Jones、Daniel B. Werz
DOI:10.1002/anie.201703732
日期:2017.8.21
trigger the ring-opening of the three-membered ring with formation of a new C−C bond. Treatment of these products with base under oxidative conditions resulted—through loss of methyl formate—in cyclopentannulated products with fully conjugated π systems exhibiting intensive absorptions in the visible range.
Suitable heterogeneous sulfonic acid derivatives ensure the smooth dearomatization of phenols and bare naphthalenes under mild conditions. The method uses hydrogenperoxide which is a clean oxidant, offering a convenient metal-free tool to access families of quinones derivatives in good yields and with low catalyst loadings.
A Novel and Convenient Process for the Selective Oxidation of Naphthalenes with Hydrogen Peroxide
作者:Feng Shi、Man Kin Tse、Matthias Beller
DOI:10.1002/adsc.200600395
日期:2007.2.5
catalyst (Ru-PTC) system for the oxidation of naphthalene derivatives has been developed. Substituted 1,4-quinones are obtained in good selectivity and yield in water without the addition of any organic solvent and acid. By applying the optimized conditions the feed additive menadione (vitamin K3) is obtained from 2-methylnaphthalene with 64 % yield and 73 % selectivity.
Molecular Engineering of Chromophores to Enable Triplet–Triplet Annihilation Upconversion
作者:Kealan J. Fallon、Emily M. Churchill、Samuel N. Sanders、James Shee、John L. Weber、Rinat Meir、Steffen Jockusch、David R. Reichman、Matthew Y. Sfeir、Daniel N. Congreve、Luis M. Campos
DOI:10.1021/jacs.0c06386
日期:2020.11.25
report up to 40-fold improvements in upconversion quantum yields using molecularengineering to selectively tailor the relative energies of the lowest singlet and triplet excited states, enhancing the yield of triplet-triplet annihilation and promoting radiative decay of the resulting singlet exciton. Using this general and effective strategy, we obtain upconversion yields with red emission that are among