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991.
Jingtao Dai Ying Wang Yukou Du Guoqing Di 《Journal of Dispersion Science and Technology》2013,34(2):205-208
Bimagnetic Pt3Co/Fe3O4 nanocomposite is synthesized in aqueous solution. The nanoparticles are characterized with TEM, FTIR, and magnetic measurements. The as‐synthesized nanocomposite exhibits ferromagnetic properties at room temperature due to the exchange coupling between Pt3Co and Fe3O4. Magnetic properties of Pt3Co/Fe3O4 nanoparticle can be tuned by varying of the molar ratio of iron to platinum. Pt3Co/Fe3O4 nanoparticles exhibit higher saturation magnetization when the molar ratio of iron to platinum is 1. 相似文献
992.
The development of an asymmetric gold-catalysed dihydroalkoxylation strategy for the synthesis of the 3′H-spiro[chroman-2,1′-isobenzofuran] spiroacetal ring system 5 is described. Spiroacetal was generated in up to 87:13 enantiomeric ratio using chiral gold–phosphine complexes and chiral silver phosphate Ag(S)-TRIP. 相似文献
993.
Mohammad Ghaffarzadeh Mohammad Bolourtchian Zohreh Hassanzadeh Fard Mohammad Reza Halvagar Farshid Mohsenzadeh 《合成通讯》2013,43(14):1973-1981
One‐step microwave‐assisted synthesis of phenylacetylenes 2a–j from the corresponding ketones 1a–j in the presence of a new reagent, PCl5–pyridine, is described. The reaction is carried out under a simple operational and experimental procedure, avoiding the use of the complicated and harsh multistep reaction. 相似文献
994.
A general and practical one‐pot synthesis of naphthopyran derivatives using hexadecyltrimethylammonium bromide (HTMAB) as catalyst (10 mol%) is described. This method provides several advantages such as neutral conditions, high yields and simple workup procedure. The catalyst is low cost, facile, active, environmentally friendly, and reusable. In addition, water is chosen as a green solvent. 相似文献
995.
Jacek Grodner 《合成通讯》2013,43(7):919-924
The main component of the sex pheromone of many lepidopteran pests, (2E,13Z)‐2,13‐octadecadienyl acetate (1), has been synthesized following a simple route using 12‐(2‐tetrahydropyranyloxy)‐1‐dodecyne (2) as the starting material. 相似文献
996.
The microwave‐promoted acid‐catalyzed rearrangement of morphine (1), codeine (2), and thebaine (3) was investigated. In all cases, a significant improvement in the yields were achieved compared to the traditional techniques. R(‐)‐Apomorphine (4), which is a clinically important dopamine agonist, was synthesized from morphine (1) in 75% yield. 相似文献
997.
Abstract A series of enantiomerically pure (Z)-(?)-4-(1′-alkyloxy-1′-alkyloxycarbonyl-methylidene)-5(R)-[(1R)-menthyloxy]-γ-butyrolactones were synthesized and characterized in good to excellent yields via O-alkylation of (4R,5R)-(?)-4-ethoxyoxalyl-5-[(1R)-menthyloxy]-γ-butyrolactone with alkyl halides in the presence of K2CO3 in acetone at room temperature. 相似文献
998.
《合成通讯》2013,43(10):1863-1870
Abstract An efficient and high‐yielding one‐pot synthesis of 1,2,4‐oxadiazoles from carboxylic acids and amidoximes is described. Activation of the carboxylic acid using hydroxybenzotriazole (HOBt) and EDC/HCl followed by reaction with an amidoxime generates an oxime ester. Without isolation, the oxime ester is dehydrated to give the oxadiazole ring. 相似文献
999.
Treatment of N-tosyl-1-aryl-1,2,3,4-tetrahydro-isoquinolines or N-tosyl-1-aryl-1,2,3,4-tetrahydro-β-carbolines with a strong base such as NaOH or KOH at 70 °C in dimethylsulfoxide (DMSO) produced 1-aryl-3,4-dihydroisoquinolines or 1-aryl-3,4-dihydro-β-carbolines in good yields via mild and regiospecific β-eliminations. A dramatic solvent effect was observed, DMSO was crucial for the reactions. The temperature is also crucial for the reactions and should be kept between 60 and 80 °C. 相似文献
1000.
Total synthesis of α-elvucitabine was achieved in 26% overall yield by a concise nine-step procedure starting from L-lyxose, with trimethylsilyl trifluoromethaneoulfonate (TMSOTf)–mediated stereocontrolled α-N-glycosidation and olefination through Barton–McCombie deoxygenation being the key steps, and the stereochemistry of the product was determined by nuclear Overhauser effect spectroscopy. 相似文献