نتایج جستجو برای: good yields

تعداد نتایج: 506625  

Journal: :iranian journal of catalysis 2011
farid rohandeh dariush saberi khodabakhsh niknam

sulfuric acid ([3-(3-silicapropyl)sulfanyl]propyl]ester (saspspe) is employed as a recyclable catalyst for the silylation of hydroxyl groups. a good range of primary, secondary alcohols and phenolic hydroxyl groups were effectively converted into their corresponding trimethylsilyl ethers with hexamethyldisilazane in the presence of catalytic amounts of saspspe at room temperature with short rea...

Journal: :Journal of the American Chemical Society 2010
Derek J Schipper Marieke Hutchinson Keith Fagnou

The rhodium(III)-catalyzed hydroarylation of internal alkynes is described. Good yields are obtained for a variety of alkynes, and excellent regioselectivity is observed for unsymmetrically substituted alkynes. The reaction also gives good yields for a range of arenes. Preliminary mechanistic investigations suggest that this reaction proceeds through arene metalation with the cationic rhodium c...

Journal: :Journal of the American Chemical Society 2006
Sulagna Paul Ghayoor A Chotana Daniel Holmes Rebecca C Reichle Robert E Maleczka Milton R Smith

Ir-catalyzed borylation of 2-substituted indoles selectively yields 7-borylated products in good yields. N-Protection, required for previous functionalizations of 2-substituted indoles, is unnecessary.

Cellulose sulfuric acid is an efficient metal-free catalyst for the synthesis of 1,3,5-trisubstituted pyrazoles via the condensation of 1,3-diketones and hydrazines. The reaction was carried out in Solvent-free condition at room temperature and the products were isolated in good to excellent yields. Mild reaction conditions, as well as ease of operation and workup are some advantages of the pro...

Elham Fereidooni Nourallah Hazeri

Trichloroacetic Acid (TCA) was used as an efficient catalyst for the synthesis of highly functionalized piperidines via a one-pot five-component reaction of aromatic amines, aromatic aldehydes and β-keto esters in MeOH at room temperature. The remarkable advantages offered by this method are good yields, simple procedure, short reaction times, no need to column chromatography and an easy wo...

Akbar Saeidniya Farnaz Abolfazli- Khosroshahi

The synthesis and characterization a new derivatives of 2'-iodo-meta terphenyl from the reaction ofexcess aryl-Grignard and 2, 6- dichloroiodobenzene with quenching of m-terphenyl-2'-magnesiumbromide by iodine is reported. Via the reactions three carbon-carbon bonds are constructed and mterphenylsare obtained in good yields.

Michael addition of pyrimidine and purine nucleobases to substituted as well as unsubstituted α,β-unsaturated esters efficiently proceeds in the presence of catalytic amount of zinc oxide in ionic liquid 1-butyl-3-methylimidazolium bromide (ZnO/[bmim]Br) under microwave irradiation to afford carboacyclic nucleosides, as biologically important compounds, in good to excellent yields and in short ...

Hassan Tajik, Khodabakhsh Niknam Somayeh Karimian

In this research, different alcohols and phenols are subjected to the reaction with HMDS in the presence of ionic liquid and silica-supported catalysts. Silylation was accomplished under mild reaction conditions at room temperature in short reaction times and good to excellent yields.

Atena Azin Narges Taheri soheil sayahi

In this study, we reported facile and efficient synthesis of 2-amino-4H-chromenes that catalyzed by polystyrene-supported 1-methylimidazolium tetrachloroferrateas. The synthesis proceeds with various aldehydes under mild conditions and afford the target products with good to high yields.

Ardeshir Khazaei Bijan Roodpeyman Ebrahim Mehdipour

Poly(p-N-chlorostyrenesulphonamide) synthesized via direct chlorination of poly[(p-styrene) sulphonamide], can be used for selective chlorination of aromatic compounds. Aromatic rings of the anisole, p-xylene, ethylbenzene and toluene are chlorinated with good yields. The polymer can be recovery, rechlorinated and reused several times.

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید