The synthesis of novel fused heterocycles is based on reactions proceeding by the mechanism of the tert-amino effect, which generalizes cyclization of certain derivatives of 3-methyl-1-phenyl-2-pyrazolin-5-ones. Using this strategy a variety of fused heterocycles is obtained by the Knoevenagel condensation of 5-tert-amino-3-methyl-1-phenylpyrazolone-4-carboxal-dehyde 3 with active methylene com...

An efficient approach for the synthesis of functionalized 4-substituted-2-amino-3-cyano-4H-chromenes moderate to high yields (up to 98%) has been achieved via a tandem K2CO3 catalyzed conjugate addition-cyclization reaction of malononitrile and a range of Knoevenagel adducts previously formed from oxindole, pyrazolone, nitromethane, N,N-dimethylbarbituric acid or indanedione. This methodology d...

Compounds incorporating the tetrathiafulvalene (TTF) donor unit and one or two cyanoethynylethene (CEE) acceptor units were prepared by Knoevenagel condensations of highly unstable, TTF-linked propargylic aldehyde or ketone derivatives. The resulting TTF-CEEs are very strong chromophores with low-energy end-absorptions beyond 900 nm. The molecules experience reversible oxidations of the TTF uni...

We have synthesized a new family of directly-fused bisBODIPY BBP 1 through a key FeCl3-mediated intramolecular oxidative cyclodehydrogenation reaction and its derivatives 2 and 3 from the Knoevenagel reaction. These dyes display effective expansion of π-conjugation over the two BODIPYs due to their locked coplanar conformation, showing intriguing electrochemical and spectroscopic properties, su...

A new non-interpenetrating 3D metal-organic framework {[Ni4(μ6-MTB)2(μ2-H2O)4(H2O)4]·10DMF·11H2O}n (DMF = N,N'-dimethylformamide) built from nickel(ii) ions as connectors and methanetetrabenzoate ligands (MTB(4-)) as linkers has been synthesized and characterized. The single crystal X-ray diffraction showed that complex exhibits CaF2-like fluorite structure topology and four types of 3D channel...

Efficient and one-pot synthesis of 1,8-dioxo-octahydroxanthenes was described by Knoevenagel condensation, Michael addition and cyclodehydration of dimedone. This reaction was carried out through condensation of dimedone and various aromatic aldehydes in the presence of task-specific Brønsted acidic ionic liquid under solvent free conditions. The catalyst could be recycled five times without si...

A series of 3-methylidene-1H-indol-2(3H)-ones substituted with a 5- or 6-pentafluorosulfanyl group has been synthesized by a Knoevenagel condensation reaction of SF5-substituted oxindoles with a range of aldehydes. The resulting products were characterized by X-ray crystallography studies and were tested for biological activity versus a panel of cell lines and protein kinases. Some exhibited si...

A simple methodology for encapsulating ca. 10 nm-sized superparamagnetic Fe3O4 nanoparticles in zeolitic imidazolate frameworks (ZIF-8) crystals was developed. The corresponding Fe3O4@ZIF-8 heterostructured material exhibits bifunctional properties with both high magnetization (Fe3O4) and high thermal stability, large specific surface, and catalytic properties (ZIF-8). The Fe3O4@ZIF-8 catalyst ...

The synthesis of a small library of dihydrouracils spiro-fused to pyrrolidines is described. These compounds are synthesized from beta-aryl pyrrolidines, providing products with the 2-arylethyl amine moiety, a structural feature often encountered in compounds active in the central nervous system. The b-aryl pyrrolidines are synthesized through a three-step methodology that includes a Knoevenage...

The synthesis of two poly(p-phenylenevinylene) oligomers (oPPV) laterally substituted by phthalocyanines (Pc) is described. The preparation of Pc-based oligomers and was accomplished by means of Knoevenagel and Wadsworth-Horner-Emmons reactions, respectively. Diformylphthalocyanine was employed as a monomer in these reactions, thus providing functionalised conjugated oligomers upon reaction wit...