فهرس المقالات 4H-Pyran

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  1 - Sodium Bismuthate: An Efficient Catalyst for the One-pot Synthesis of Biologically Active Spiro[4H-pyran] Derivativesunder Solvent-free Conditions
  Farzaneh Mohamadpour Malek Taher Maghsoodlou Reza Heydari Mojtaba Lashkari
  An efficient sodium bismuthate (NaBiO3) synthesis of biologically active spiro[4H-pyran]derivatives has been accomplished via one-pot three-condensation of isatin/acenaphthequinone, malononitrile and different reagents including 1,3-dicrbonyl compounds, α-naphthol أکثر

  An efficient sodium bismuthate (NaBiO3) synthesis of biologically active spiro[4H-pyran]derivatives has been accomplished via one-pot three-condensation of isatin/acenaphthequinone, malononitrile and different reagents including 1,3-dicrbonyl compounds, α-naphthol and 4-hydroxycumarin under solvent-free conditions. The notable advantages of the present procedure are: eco-friendly, environmentally benign nature,low-cost and non-toxic catalyst, simplicity of operation with no necessity of chromatographicpurification steps, short reaction times, good to high yields and solvent-free conditions. تفاصيل المقالة
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  2 - High Catalytic Ability of Fe3O4/EDTA Magnetic Nanocatalyst in Comparison with Various Deep Eutectic Solvents for One-Pot Synthesis of 4H-Pyrans
  hossein tavakol Dana Shahabi
  10.22034/jna.2018.543347.1033
  In this work, various 3-cyano-4-aryl-4H-pyran derivatives were prepared efficiently through a one-pot, multicomponent synthesis between aromatic aldehyde, malononitrile and acetophenone derivatives or ethyl acetoacetate using Fe3O4/EDTA magnetic nanocatalyst and ethanol أکثر

  In this work, various 3-cyano-4-aryl-4H-pyran derivatives were prepared efficiently through a one-pot, multicomponent synthesis between aromatic aldehyde, malononitrile and acetophenone derivatives or ethyl acetoacetate using Fe3O4/EDTA magnetic nanocatalyst and ethanol as solvent. The reactions were completed at room temperature in 10 min using 5 mg of catalyst and 2 mL of solvent to prepare 1 mmol of the product. The employed catalyst is consisted of magnetite nanoparticles core, which coated with EDTA to modify its surface and prevent the aggregation. In addition, the catalytic abilities of different deep eutectic solvents (DESs) such as choline chloride/tin (II) chloride, choline chloride/zinc chloride and choline chloride/urea were compared with the nanomagnetic catalyst via this synthesis. The nanomagnetic catalyst showed higher ability in comparison with various DESs for the title reaction. The employed nanomagnetic catalyst has been recycled 4 time without important loss of its activity which show its high efficiency and small leaching. تفاصيل المقالة
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  3 - High Catalytic Ability of Fe3O4/EDTA Magnetic Nanocatalyst in Comparison with Various Deep Eutectic Solvents for One-Pot Synthesis of 4H-Pyrans
  Dana Shahabi hossein tavakol
  10.22034/jna.2018.541849
  In this work, various 3-cyano-4-aryl-4H-pyran derivatives were prepared efficiently through a one-pot,multicomponent synthesis between aromatic aldehyde, malononitrile and acetophenone derivativesor ethyl acetoacetate using Fe3O4/EDTA magnetic nanocatalyst and ethanol a أکثر

  In this work, various 3-cyano-4-aryl-4H-pyran derivatives were prepared efficiently through a one-pot,multicomponent synthesis between aromatic aldehyde, malononitrile and acetophenone derivativesor ethyl acetoacetate using Fe3O4/EDTA magnetic nanocatalyst and ethanol as solvent. The reactionswere completed at room temperature in 10 min using 5 mg of catalyst and 2 mL of solvent to prepare1 mmol of the product. The employed catalyst has consisted of magnetite nanoparticles core, whichcoated with EDTA to modify its surface and prevent the aggregation. In addition, the catalytic abilitiesof different deep eutectic solvents (DESs) such as choline chloride/tin (II) chloride, choline chloride/zinc chloride and choline chloride/urea were compared with the nanomagnetic catalyst via thissynthesis. The nanomagnetic catalyst showed higher ability in comparison with various DESs for thetitle reaction. The employed nanomagnetic catalyst has been recycled 4 times without important lossof its activity which shows its high efficiency and small leaching. تفاصيل المقالة
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  4 - Introduction of Brönsted acidic ionic liquid supported on nanoporous Na+-montmorillonite as an efficient catalyst for the synthesis of 2-amino-tetrahydro-4H-pyrans
  Farhad Shirini Masoumeh Makhsous Mohadeseh Seddighi
  Nanoporous sodium montmorillonite clay (Na+-MMT) was used as a support for the immobilization of 1-methyl-3-(trimethoxysilylpropyl)-imidazolium hydrogen sulfate (Na+-MMT-[pmim]HSO4). This catalyst showed excellent catalytic activity for the preparation of 2-amino-3-cyan أکثر

  Nanoporous sodium montmorillonite clay (Na+-MMT) was used as a support for the immobilization of 1-methyl-3-(trimethoxysilylpropyl)-imidazolium hydrogen sulfate (Na+-MMT-[pmim]HSO4). This catalyst showed excellent catalytic activity for the preparation of 2-amino-3-cyano-5-oxo-5,6,7,8-tetrahydro-4H-benzopyrans via three-component reactions between aldehydes, dimedone and malononitrile. The procedure gave the products in high yields within short reaction times. Also, this catalyst can be reused at least for five times without loss of its catalytic activity. All the products were characterized using melting point, IR, 1H NMR and 13C NMR and were identified by comparison of their spectra with those of authentic samples. تفاصيل المقالة
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  5 - La2O3 as a very effective double‌-functional catalyst for the production of 2-amino-4-aryl-4H-pyrans and Pyrazolopyranopyrimidines
  Alireza Kohzadian Rohollah Fathollahi Mostafa Karami Esmail Korani Abdolkarim Zare
  10.30495/ijc.2023.1990117.2017
  Lanthanum (III) oxide (La2O3) was applied as an efficient bifunctional catalyst to develop a new methodology in the production of 2-amino-4-aryl-4H-pyrans and pyrazolopyranopyrimidines in the absence of solvent. In both synthetic protocol, due to the dual functionality أکثر

  Lanthanum (III) oxide (La2O3) was applied as an efficient bifunctional catalyst to develop a new methodology in the production of 2-amino-4-aryl-4H-pyrans and pyrazolopyranopyrimidines in the absence of solvent. In both synthetic protocol, due to the dual functionality of lanthanum (III) oxide (i.e. having basic and acidic Lewis sites), it was very useful and general, and plausible mechanisms were presented in support of this generality and high capability. The current protocol featured environmentally friendly conditions, the ability to recycle and reuse the heterogeneous catalyst up to 6 times, providing products in short times with high yields, easy work-up and no need for difficult steps of catalyst synthesis by using a commercially available catalyst, which makes it an appealing route for the preparation of these derivatives. تفاصيل المقالة