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991.
Venkataprasad Jalli Suvratha Krishnamurthy Hiroyoshi Kawasaki Tetsuji Moriguchi Akihiko Tsuge 《合成通讯》2013,43(19):2216-2226
An efficient and facile method for the synthesis of novel spiro[indole-2,2′-pyrroles] from N-methyl-3-isatin imines, t-butyl isocyanide, and dialkyl acetylenedicarboxylate has been achieved by [3 + 2] cyclo addition reaction. All the products were purified by column chromatography as yellow solids and confirmed with 1H NMR, 13C NMR, fast atom bombardment, mass, and infrared. Compound 11 was further confirmed with x-ray analysis. 相似文献
992.
A compact three-step synthesis of a new fused bisindole system isomeric with the heterocyclic skeleton present in the marine natural product iheyamine A has been achieved. The structure of the synthetic product was confirmed by a single-crystal X-ray structure. 相似文献
993.
ZrOCl2 · 8H2O catalyzes the one-pot synthesis of β′-acetamido-β-dicarbonyl compounds in high yields from aldehyde, enolizable β-dicarbonyl compound, acetyl chloride, and acetonitrile in solvent as well as in solvent-free conditions. β′-Acetamido-β-ketoesters are formed in moderate to exclusive pref-diastereoselectivity. 相似文献
994.
Timur I. Savchenko Olexiy V. Silin Sergiy M. Kovalenko Vladymir I. Musatov Viktor M. Nikitchenko 《合成通讯》2013,43(8):1321-1330
The interaction of 3‐phenyl‐1H‐pyrazolo[4.3‐c]quinoline with alkylating agents in the presence of NaH leads mainly to N1‐substituted derivatives. The regioselectivity of the reaction has been studied using AM1 semi‐empirical calculations in the isolated molecule approximation. 相似文献
995.
A convenient, fast, efficient, and ecofriendly synthesis of metal‐free phthalocyanines from various substituted phthalonitriles in different hydroxyalkylammonium ionic liquids in the presence of 1,8‐diazabicyclo‐[5,4,0]‐undec‐7‐ene (DBU) is reported in moderate yields. The effect of concentration of DBU and temperature on the synthesis of phthalocyanine in N‐(2‐hydroxyethyl)‐N,N‐dimethylbutylammonium bromide ionic liquid has been examined, and the ionic liquid has been recovered and reused conveniently. 相似文献
996.
A. Ebenezer Martin 《合成通讯》2013,43(11):1778-1783
A novel method for the synthesis of 6,12‐dihydro‐2‐methylindolo[2,3‐b]carbazol‐6‐ones was developed from 1‐oxo‐2,3,4,9‐tetrahydro‐1H‐carbazol‐1‐one through methyl 6‐methyl‐2‐(1‐oxo‐2,3,4,9‐tetrahydro‐1H‐carbazol‐2‐yl)oxoacetate in good yields. This method provides an alternative path for the synthesis of this product using 2‐hydroxy methylene‐2,3,4,9‐tetrahydro‐1H‐carbazol‐1‐one. 相似文献
997.
We report here an efficient method for the synthesis and characterization of the room-temperature ionic liquid 1,3-di-n-butylimidazolium tribromide ([BBIm]Br3) (2) and its application as an efficient reagent and solvent for regioselective bromination of arylamines and phenols under mild conditions. The bromination was carried out in the absence of organic solvents, and in most cases, the only extraction solvent needed was water. The spent 1,3-di-n-butylimidazolium bromide (1) was easily recycled. 相似文献
998.
Farag A. El-Essawy 《合成通讯》2013,43(6):877-887
8,10-Dimethyl-3-(unsubstituted, methyl, ethyl, n-butyl, phenyl)-4-hydroxypyrido[2′,3′:3,4]pyrazolo[1,5-a]pyrimidin-2(1H)-ones and 3-(2-hydroxyethyl)-2,8,10-trimethylpyrido[2′,3′:3,4]pyrazolo[1,5-a]pyrimidin-4-ol were synthesized by cyclocondensation of 3-amine-4,6-dimethyl-1H-pyrazolo[3,4-b]pyridine with ethyl malonates and α-acetyl-γ-butyrlolactone. Dichloro- and diazido- derivatives were obtained from the reaction of pyridopyrazlopyrimidine derivatives with POCl3 followed by NaN3. The tetrahetrocyclic systems were formed by cyclization of 4-chloro-3-(2-chloroethyl)-2,8,10-trimethylpyrido[2′,3′:3,4]pyrazolo[1,5-a]pyrimidine with the appropriate primary amines. The structures of all compounds were established by NMR and mass spectra. 相似文献
999.
A simple and efficient method for the preparation of novel C‐3 vinylic derivatives of imidazo[1,2‐a]pyridines has been developed by the reaction of imidazo [1,2‐a]pyridines with appropriate aliphatic aldehydes in acetic acid in a sealed tube. 相似文献
1000.
Liladhar Waykole Mahavir Prashad Stephen Palermo Oljan Repic Thomas J. Blacklock 《合成通讯》2013,43(12):2159-2163
A practical synthesis of 2-(bromomethyl)naphthalene (1), by selective benzylic bromination of 2-methylnaphthalene (2), with bromine in heptane in the presence of lanthanum acetate hydrate is described. 相似文献