No abstract

A simple and efficient synthesis of 1,3,4,5‐trisubstituted‐1H‐imidazole‐2(3H)‐thiones via a one‐pot three‐component reaction of benzoin with isothiocyanates and aromatic amines in the presence of glacial acetic acid and heteropolyacid is described. All synthesized compounds were characterized on the basis of their spectral and microanalytical data.

A convenient and efficient method for the synthesis of pyrazolo [3,4-d]pyrimidin-4-ones via heterocyclization reaction of 5-amino-1H-pyrazole-4-carboxamides with triethyl orthoesters using two Brønsted-acidic ionic liquids, 3-methyl-1-(4-sulfonic acid)butylimidazolium hydrogen sulfate [MIM ＋ (CH 2 ) 4 SO 3 H][ 4 HSO -] or N-(4-sulfonic acid)butyl triethylammonium hydrogen sulfate [Et 3 N ＋ (CH 2 ) 4 SO 3 H][ 4 HSO -], as efficient homogeneous catalysts under solvent-free conditions is described.

ChemInform Abstract The chloroarene complex (Ia) reacts with the carbonylferrate (II) to give (III), whereas analogous complexes (V) are prepared starting with (Ib). The use of (Ia) only leads to reductive dehalogenation of the arene complex. The classical η6-arene structure as opposed to the alternate possible η5-cyclohexadienide carbene valence form is assigned by spectroscopic data and confirmed by an X-ray analysis of (Vb) (Pca21, Z=4).

Some new 4‐(aryl)‐2,6‐di‐2‐naphthylpyridines and 4‐(aryl)‐2,6‐di‐2‐thienylpyridines have been prepared through three‐component condensation of 2‐acetylnaphthalene or 2‐acetylthiophene, aromatic aldehydes, and ammonium acetate in presence of 1‐(4‐sulfonylbutyl) pyridinium hydrogensulfate [(CH2)4SO3HPy][HSO4], a Brønsted acidic ionic liquid as a green and reusable catalyst in solvent‐free conditions. Also some new 4,4'‐(1,4‐phenylene)‐bis‐(2,6‐di‐aryl pyridine) was prepared. J. Heterocyclic Chem., (2011).