24405-31-0Relevant academic research and scientific papers
Cross-linked polystyrene-TiCl4 complex as a reusable Lewis acid catalyst for solvent-free Knoevenagel condensations of 1,3-dicarbonyl compounds with aldehydes
Rahmatpour, Ali,Goodarzi, Niloofar
, p. 24 - 31 (2019/03/08)
Cross-linked polystyrene copolymer beads with the average particle size in the range of (50–80 mesh size) were prepared by a new method, characterized and functionalized with titanium tetrachloride to afford the corresponding polystyrene?titanium tetrachloride complex in one step reaction and characterized by FT-IR, UV, TGA, DSC, XRD, SEM, BET. This polymer metal complex (PS/TiCl4) was used as a heterogeneous, recoverable, reusable Lewis acid for solvent-free Knoevenagel condensations of 1,3-diketones with aromatic aldehydes under green and mild conditions. The rate of reactions was found to decrease with an increasing percentage of crosslinking and the mesh size of the copolymer beads. This complex showed good stability and catalytic activity in the Knoevenagel reactions.
Design, synthesis and spectroscopic and crystallographic characterisation of novel functionalized pyrazole derivatives: biological evaluation for their cytotoxic, angiogenic and antioxidant activities
Dileep Kumar, Achutha,Bharath, Srinivasan,Dharmappa, Rekha N.,Naveen, Shivalingegowda,Lokanath, Neratur Krishnappagowda,Ajay Kumar, Kariyappa
, p. 5635 - 5652 (2018/04/30)
Abstract: The current study presents the synthesis of functionalized pyrazoles (18–29) through 3 + 2 annulation reaction of ethyl 2-(arylidene)-3-oxobutanoates (8–13) with phenylhydrazine hydrochlorides (14–17) in acetic acid under reflux conditions. Stru
Raman spectroscopy as a tool for monitoring mesoscale continuous-flow organic synthesis: Equipment interface and assessment in four medicinally-relevant reactions
Hamlin, Trevor A.,Leadbeater, Nicholas E.
supporting information, p. 1843 - 1852 (2013/10/22)
An apparatus is reported for real-time Raman monitoring of reactions performed using continuous-flow processing. Its capability is assessed by studying four reactions, all involving formation of products bearing α,β-unsaturated carbonyl moieties; synthesi
A simple method for the preparation of functionalized trisubstituted alkenes and α,β,γ,δ-unsaturated carbonyl compounds by using natural amino acid l-tryptophan
Hu, Ying,He, Yan-Hong,Guan, Zhi
scheme or table, p. 656 - 659 (2010/11/05)
Primary natural amino acid l-tryptophan was used, for the first time, as a catalyst in Knoevenagel condensations of aliphatic, aromatic, hetero-aromatic and α,β-unsaturated aldehydes with less reactive acetylacetone and ethyl acetoacetate. The reactions were carried out at room temperature and gave good yields. It is a convenient entry for preparation of functionalized trisubstituted alkenes and α,β,γ,δ-unsaturated carbonyl compounds.
SYNTHESIS OF HETEROCYCLIC COMPOUNDS. XXXVI. PREPARATION OF ALKYL SUBSTITUTED PYRANCARBONITRLES.
Soto, Jose L.,Seoane, Carlos,Martin, Nazario,Quinteiro, Margarita
, p. 1 - 6 (2007/10/02)
The cyclization of the ketonitriles obtained from the reaction of suitably substituted propenones with propanedinitrile leads to alkyl substituted 4H-pyrans.Some of the starting propenones had to be prepared by base promoted opening of an isoxazole ring in the presence of an aldehyde.An exception to the general synthesis is also reported.
