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21.
A simple and efficient method for the iodination of aromatic amines using pyridinium iodochloride (PyICl) in methanol as solvent is reported. Mild reaction conditions, short reaction time, and good to excellent yields of the product are the noteworthy advantages of the method. Pyridinium iodochloride is an efficient solid iodinating reagent and can be handled safely. 相似文献
22.
Allylic amines are synthesized in good to excellent yields by treatment of aziridine-2-alcohols with PPh3/I2/imidazole in THF as solvent under mild conditions. 相似文献
23.
Subhash C. Jain Pankaj Khanna Sunita Bhagat Manish Jain Rajeev Sakhuja 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1829-1839
The reaction of indol-2,3-diones ( 1a–i ) with 5-aminoindazole ( 2 ) has resulted in the formation of hitherto unknown 3-(indazol-5-yl)iminoindol-2-ones ( 3a–i ) in quantitative yields which, on 1,3-dipolar cyclocondensation with mercaptoacetic acid ( 4 ), has afforded a series of new spiro heterocycles, 3′-(indazol-5-yl) spiro[3H, indol-3, 2′ -thiazolidine]-2,4′-diones* ( 5a–i ). 相似文献
24.
Vinyl sulphides find a substantial application in organic synthesis.2 The synthetic utility of heter cyclic vinyl sulphides due to the ease in extension of heterocyclic ring3 should be more versatile, Here, we report the synthesis of isoquinolinyl vinyl sulphides from dihydrothiazolo [2, 3-a] isoquinolinium cations, depicting another use of heterocycles in organic synthesis.4 相似文献
25.
Total synthesis of (Z) pulchellalactam, a CD protein tyrosine phosphatase inhibitor, from commercially available methallyl chloride employing ring‐closure metathesis (RCM) as a key step is described. 相似文献
26.
Ashok Kumar Subhash Thota Sri Sivakumar Shashank Priya Jitendra Kumar 《Journal of Sol-Gel Science and Technology》2013,68(1):46-53
The Mg–Ce–O powder are shown to contain periclase-type MgO and/or fluoride-type cerium oxide (CeO2) depending upon the composition (x) defined by Ce/(Ce + Mg) atomic ratio. Lattice contraction of pariclase phase of MgO (average crystallite size ~8.8 nm) at Ce content of ‘x’ = 0.20 in comparison to pure MgO (crystallite size ~9.5 nm) has been realized due to oxygen vacancy formation. The optical band gap values of CeO2 varies (3.0–3.2 eV) due to oxygen vacancy formation in CeO2 phase, crystallite size and/or Ce3+/Ce4+ ratio. Further, the addition of Ce has shown to reduce the physisorption and chemisorption of water significantly as reflected by (1) suppression of related absorption peaks and (2) absence of magnesium hydroxide, Mg(OH)2, bands in Fourier transform infrared spectra. 相似文献
27.
The first report of natural l-vasicine as tridentate chiral ligand for the enantioselective addition of diethylzinc to a variety of aliphatic and aromatic aldehydes is described. The ligand generates R-isomer of the secondary alcohols upto 98% ee. The quinazoline structure possibly imparts rigidity to the ligand and hence, consistently high enantioselectivity. The importance of the quinazoline ring was also supported by the reaction with other related ligands, partially lacking the structural features, thus resulting in poor enantioselectivity. 相似文献
28.
Oximes of ketones and aldehydes are efficiently deprotected with glyoxylic acid in an aqueous medium at room temperature. Oximes can be cleaved selectively in the presence of a TBDMS group. This method is high yielding, fast, clean, safe, cost effective, and therefore very suitable for practical organic synthesis. 相似文献
29.
Dr. Aloysius Siriwardena Kiran Kumar Pulukuri Pancham S. Kandiyal Dr. Saumya Roy Dr. Omprakash Bande Dr. Subhash Ghosh Dr. José Manuel Garcia Fernández Dr. Fernando Ariel Martin Dr. Jean‐Marc Ghigo Dr. Christophe Beloin Dr. Keigo Ito Dr. Robert J. Woods Dr. Ravi Sankar Ampapathi Dr. Tushar Kanti Chakraborty 《Angewandte Chemie (International ed. in English)》2013,52(39):10221-10226
30.