Results 11 to 20 of about 200 (108)

Pentafluoropropionic Acid: An Efficient and Metal‐Free Catalyst for the One‐Pot Synthesis of Tetrahydrobenzo[b]pyran Derivatives

Journal of Chemistry, Volume 2014, Issue 1, 2014., 2014
Pentafluoropropionic acid (PFPA) efficiently catalyzes the one‐pot, three‐component reaction of aromatic aldehyde, malononitrile, and dimedone to yield tetrahydrobenzo[b]pyran derivatives in high yields. This method is of great value because of its easy processing, short reaction time, environmentally, and high yields.
Naser Montazeri, Taghva Noghani, Mona Ghorchibeigy, Rozita Zoghi, Mohamed Afzal Pasha   +4 more
wiley   +1 more source

Ionic Liquids: Synthesis and Applications in Catalysis

Advances in Chemistry, Volume 2014, Issue 1, 2014., 2014
Ionic liquids have emerged as an environmentally friendly alternative to the volatile organic solvents. Being designer solvents, they can be modulated to suit the reaction conditions, therefore earning the name “task specific ionic liquids.” Though primarily used as solvents, they are now finding applications in various fields like catalysis ...
Rajni Ratti, Hideaki Shirota
wiley   +1 more source

Microwave‐Assisted Three‐Component “Catalyst and Solvent‐Free” Green Protocol: A Highly Efficient and Clean One‐Pot Synthesis of Tetrahydrobenzo[b]pyrans

Organic Chemistry International, Volume 2014, Issue 1, 2014., 2014
A green and highly efficient method has been developed for the one‐pot synthesis of tetrahydrobenzo[b]pyrans via a three‐component condensation of aldehydes, 1,3‐cyclic diketones, and malononitrile under MW irradiation without using any catalyst and solvent.
Sougata Santra, Matiur Rahman, Anupam Roy, Adinath Majee, Alakananda Hajra, Ashraf Aly Shehata   +5 more
wiley   +1 more source

Synthesis of Fe 3 O 4 /Eggshell Nanocomposite and Application for Preparation of Tetrahydrobenzo[b]Pyran Derivatives

Iranica Journal of Energy and Environment, 2017
This work is reported on the synthesis of Fe3O4/eggshell nanocomposites in the absence of any stabilizer or surfactant. Fe3O4 magnetic nanoparticles were established on the egg shell nano-composite. The nanocompositeshave shown high catalytic activities in the synthesis of Tetrahydrobenzo[b]pyran. These derivatives were synthesized via an one‐pot three‐
M. Naghizadeh, P. Mohammadi, H. Sheibani, M. A. Taher   +3 more
openaire   +2 more sources

An Efficient Synthesis of Tetrahydrobenzo[b]pyran Derivatives Using Sulfonic Acid Functionalized Silica as an Efficient Catalyst

Journal of Chemistry, Volume 8, Issue 1, Page 293-299, 2011., 2011
Tetrahydrobenzo[b]pyran derivatives were efficiently synthesized by the reaction of appropriated aromatic aldehydes, malononitrile and dimedone in the presence of SiO2‐Pr‐SO3H as a nanoporous and recoverable solid acid catalyst, in good to excellent yields.
Ghodsi Mohammadi Ziarani, Alireza Abbasi, Alireza Badiei, Zeinab Aslani   +3 more
wiley   +1 more source

An Efficient and Convenient Approach to Synthesis of Tetrahydrobenzo[b]pyran Derivatives Using Tetrabutylammonium Bromide as Catalyst

Journal of Chemistry, Volume 6, Issue S1, Page S466-S472, 2009., 2009
An efficient and convenient approach to the synthesis of 2‐amino‐3‐cyano‐4‐aryl‐7,7‐dimethyl‐5‐oxo‐4H‐5, 6, 7, 8‐ tetrahydro benzo[b]pyran derivatives using tetrabutylammonium bromide (TBABr) as the catalyst is described. This method provides several advantages such as neutral conditions, high yields and simple work procedure.
S. Gurumurthi, V. Sundari, R. Valliappan
wiley   +1 more source

An Environmentally Benign Protocol for Aqueous Synthesis of Tetrahydrobenzo[b]Pyrans Catalyzed by Cost-Effective Ionic Liquid [PDF]

International Journal of Molecular Sciences, 2014
A mild, efficient, and environmentally benign protocol for the synthesis of tetrahydrobenzo[b]pyran derivatives in the presence of readily accessible, biodegradable, and choline hydroxide based ionic liquid as catalyst has been established. The key features of the reported methodology include good to excellent yields of desired products, simple work-up
Hu, Huanan, Qiu, Fangli, Ying, Anguo, Yang, Jianguo, Meng, Haiping   +4 more
openaire   +2 more sources

State‐of‐the‐Art, Insights, and Perspectives for MOFs‐Nanocomposites and MOF‐Derived (Nano)Materials

Advanced Materials, Volume 37, Issue 52, December 29, 2025.
Different approaches to MOF‐NP composite formation, such as ship‐in‐a‐bottle, bottle‐around‐the‐ship and in situ one‐step synthesis, are used. Owing to synergistic effects, the advantageous features of the components of the composites are beneficially combined, and their individual drawbacks are mitigated.
Stefanos Mourdikoudis, Subhajit Dutta, Saqib Kamal, Sergio Gómez‐Graña, Isabel Pastoriza‐Santos, Stefan Wuttke, Lakshminarayana Polavarapu   +6 more
wiley   +1 more source

Steric Effects in Benzopyran Imine‐Hemiaminal Ring–Chain Tautomerism: Tautomeric Free Energies as a Measure of Substituent Size

ChemistrySelect, Volume 10, Issue 37, October 6, 2025.
Equilibrium constants for a series of substituted benzopyranamines were determined. The calculated free energies correlate with the steric size of the substituent and compare well with a previously reported series of benzofuranamines. X‐ray crystallographic data of examples from both series offers an understanding of the steric effects and lack of ...
Benjamin D. Cavilla, Tanis Huzil, Peter W. Dibble, René T. Boeré   +3 more
wiley   +1 more source

[AcMIM]FeCl4: A Magnetically Separable Organocatalyst for the Clean Synthesis of Tetrahydrobenzo[b]pyran Derivatives

Current Organocatalysis, 2019
Background: Recently, organic synthesis using ionic liquids (ILs) via green approach has attracted considerable attention to address the problem associated with environmental pollution. Magnetization of ILs provides added advantages of separation by external magnet.
Arijit Saha, Soumen Payra, Archana Asatkar, Ashok Raj Patel, Subhash Banerjee   +4 more
openaire   +1 more source