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Ultrasound-assisted synthesis of 1,8-dioxo-octahydroxanthene derivatives catalyzed by p-dodecylbenzenesulfonic acid in aqueous media 总被引:1,自引:0,他引:1
An efficient and convenient approach to the synthesis of 3,3,6,6-tetramethyl-9-aryl-1,8-dioxo-octahydroxanthene derivatives using p-dodecylbenzenesulfonic acid (DBSA) as the catalyst (10 mol.%) under ultrasound irradiation is described. This method provides several advantages such as environment friendliness, high yields and simple work-up procedure. In addition, water was chosen as a green solvent. 相似文献
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In modem organic chemical research, 4H-benzo-[b]-pyran and their derivatives have attracted strong interest due to their useful biological and pharmacological properties. Herein, we report a clean one-pot synthesis of 2-amino-3-cyano-4-aryl-7,7-dimethyl-5-oxo-4H-5,6,7,8-tetrahydro-benzo-[b]-pyrans from aromatic aldehyde, malononitrile and 5,5-dimethyl-1,3-cyclohexadione using hexadecyl trimethyl ammonium bromide (HTMAB) as the catalyst. This method provides several advantages such as high yield, simple work-up procedure and environmental friendliness. All the products were characterized by 1H NMR and IR analyses. 相似文献
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An efficient and convenient conversion of oximes to corresponding carbonyl compounds with ozone is reported. 相似文献
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An easy preparation of trimethylsilyl ethers of alcohols and phenols with 1,1,1,3,3,3-hexamethyldisilazane(HMDS) catalysed by montmorillonite K-10 at room temperature has been carried out in excellent yields. Desilyation of trimethylsilyl ethers is catalysed by K-10 in methanol at ambient temperature in high yields. 相似文献
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The synthesis of 15α-hydroxy-15(14→8)abeo-5α,(8S)-cholestane-3,14-dione (1) fromcholesterol in ten steps was described.The key step is the intramolecular aldol condensationof 3,14-dioxo-14,15-seco-5α-cholestan-15-al (3). 相似文献
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An efficient and practical synthesis of bis(indolyl)methanes catalyzed by aminosulfonic acid under ultrasound 总被引:1,自引:0,他引:1
Synthesis of bis(indolyl)methanes via electrophilic substitution reactions of indoles with aromatic aldehydes and ketones catalyzed by aminosulfonic acid was carried out in 23-96% yield at 30-38 degrees C in EtOH aqueous solution under ultrasound irradiation. 相似文献