Results 111 to 120 of about 90,377 (200)

One-pot two-step mechanochemical synthesis of arylsulfonyl 4H-pyrans

Journal of Sulfur Chemistry, 2022
In this paper, a simple and environment-friendly protocol was developed for the synthesis of arylsulfonyl 4H-pyrans via L-proline-catalyzed one-pot two-step reaction of aromatic aldehyde with phenylsulphonyl acetonitrile and dimedone under ball-milling ...
Ling Jiang, Qingqing Lu, Qianqian Huang, Yue Cheng, Xiaohe Chu   +4 more
semanticscholar   +1 more source

One-pot synthesis of 2-amino-3-cyano-4H-pyrans and pyran-annulated heterocycles using sodium citrate as an organo-salt based catalyst in aqueous ethanol

Synthetic Communications, 2021
Sodium citrate as a highly efficient catalyst is developed for the synthesis of functionalized 2-amino-3-cyano-4H-pyrans and pyran-annulated heterocycles.
Aiborlang Thongni, Pynskhemborlang T. Phanrang, A. Dutta, R. Nongkhlaw   +3 more
semanticscholar   +1 more source

A New Basic Ionic Liquid Supported on Magnetite Nanoparticles: An Efficient Phase-Transfer Catalyst for the Green Synthesis of 2-Amino-3-Cyano-4H-Pyrans

Polycyclic aromatic compounds (Print), 2020
An efficient and straightforward procedure has been developed for the synthesis of 2-amino-3-cyano-4H-pyrans via the one-pot three-component reaction of benzaldehydes, malononitrile and 1,3-dicarbonyl compounds using a new nanomagnetite-supported ...
M. Fallah-Mehrjardi, M. Shirzadi, S. H. Banitaba   +2 more
semanticscholar   +1 more source

4H-pyrans (review)

Chemistry of Heterocyclic Compounds, 1983
Data on the chemistry of monocyclic, unsaturated, six-membered, oxygen-containing heterocycles, viz., 4H-pyrans, are correlated and systematized for the first time. The methods for their synthesis, their transformations, and spectroscopic data for them are discussed. The interest in these compounds, which has increased recently, is due to the fact that
O. V. Drygina, A. D. Garnovskii
openaire   +1 more source

Synthesis of Novel Hybrid 4H-Pyran-lipoic and 4H-Pyran-azetidine Derivatives

Synthesis, 2017
In this study, a molecular hybridization strategy was used to design and synthesize two novel series of hybrid compounds: 4H-pyran-lipoic and 4H-pyran-azetidine, employing ammonium hydroxide and involving the participation of aldehydes, malononitrile, and compounds derived from β-ketoesters to obtain the products with good yields.
Miguel Vázquez, Fernando Hernández-Borja, Leticia Contreras, Julio López, Yolanda Alcaraz, David Cruz, Samuel Estrada-Soto, Francisco Delgado   +7 more
openaire   +1 more source

ChemInform Abstract: RING TRANSFORMATIONS OF 4H‐PYRANS. PYRIDINES FROM 2‐AMINO‐4H‐PYRANS

Chemischer Informationsdienst, 1981
AbstractAus den 2‐Amino‐4H‐pyranen (I) erhält man mit Nitrosylschwefelsäure und Essigsäure die entsprechend substituierten Pyridone (II).
C. SEOANE, J. L. SOTO, P. ZAMORANO, M. QUINTEIRO   +3 more
openaire   +1 more source

Structure of 2,4,4,6-tetraphenyl-4H-pyran

Acta Crystallographica Section C Crystal Structure Communications, 1990
C 29 H 22 O cristallise dans P2 1 /c avec a=12,128, b=12,372, c=14,599A, β=105,57°, Z=4 ; affinement jusqu'a R=0,039. Le cycle 4H-pyrane est rigoureusement plan avec les cycles phenyl substitues sur les atomes C(sp 2 ) de C2 et C6. Le cycle presente une conformation bateau legerement tordue avec les angles bateau de 4,3 et 7,7° sur C(sp 2 ) et O ...
J. Vojtěchovský, J. Hašek
openaire   +1 more source

Cyclopropanation of areno-condensed 4H-pyrans with dihalocarbenes

Chemistry of Heterocyclic Compounds, 2020
The addition of dihalocarbenes to 1H-benzo[f]chromenes and 4H-chromenes gave a number of dihalotetrahydro(benzo)cyclopropa[b]-chromenes containing donor and acceptor substituents at different positions. It was found that in the case of 1,3-disubstituted 1H-benzo[f]-chromenes, the reaction proceeds diastereoselectively with the formation of trans ...
Irina А. Semenova, Vitaly А. Osyanin, Maxim R. Demidov, Dmitry V. Osipov, Yuri N. Klimochkin   +4 more
openaire   +1 more source

Synthesis of new low-viscous sulfonic acid-functionalized ionic liquid and its application as a Brönsted liquid acid catalyst for the one-pot mechanosynthesis of 4H-pyrans through the ball milling process

Journal of Molecular Liquids, 2019
In the present study, a new low-viscous sulfonic acid-functionalized ionic liquid (SAIL) viz. 4,4′-trimethylene-N,N′-sulfonic acid-dipiperidinium chloride was synthesized and characterized by FTIR, 1D and 2D NMR, and Mass spectra.
N. G. Khaligh, Taraneh Mihankhah, M. Johan   +2 more
semanticscholar   +1 more source

Synthesis of novel multi-OH functionalized ionic liquid and its application as dual catalyst-solvent for the one-pot synthesis 4H-pyrans

Journal of Molecular Liquids, 2019
In the present work, triethanolammonium 3-hydroxypropane-1-sulfonate [TEA][HPS] as a novel multi-OH functionalized ionic liquid was synthesized. [TEA][HPS] was characterized by 1HNMR, 13CNMR, FT-IR and elemental analysis. In addition to structural study,
M. Honarmand, Andromachi Tzani, A. Detsi
semanticscholar   +1 more source