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The synthesis and properties of 11,11,12,12-tetracyano-4,5-pyrenoquinodimethanes (4,5-TCNPs), a new family of isolable and air-stable o-quinodimethanes, are reported. The ortho disposition of the dicyanomethane substituents strongly polarizes the pyrene framework to promote broad and intense intramolecular charge-transfer transitions. In addition, spectroscopic studies reveal that 4,5-TCNPs violate Kasha’s rule and emit from the S2 level., Fundação para a Ciência e a Tecnologia (FCT)

A simple and efficient procedure was developed for the synthesis of multisubstituted 2-aminothiophene derivatives. In the presence of catalytic amount of imidazole, ketones or aldehydes, dicyanomethane and elemental sulfur were converted into the corresponding 2-aminothiophene derivatives in moderate to high yields in DMF at 60 °C.

It has been established that oxidation of a mixture of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and dicyanomethane or formaldehyde with manganese dioxide gives 3-hydroxymethyl-1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, the structure of which was confirmed by X-ray structural analysis. Some oxidative conversions by potassium permanganate of the product formed and its esters have been studied. These included lactamization, aromatization, and oxodihydroxylation.

Reaction of a hydroxopalladium complex bearing the TpiPr2 ligand, (TpiPr2)(py)Pd−OH (1iPr2), with active methylene compounds, X−CH2−Y 2 [dicyanomethane (2a), methyl cyanoacetate (2b), benzoylaceton...

Accurate structures have been determined for dicyanomethane, H 2 C(CN) 2 , vinyl dicyanide, H 2 CC(CN) 2 , carbonyl cyanide, OC(CN) 2 , and sulfur dicyanide, S(CN) 2 , by combining the results of electron diffraction, microwave spectroscopy and ab initio calculations. The different methods are compared. The influence of the correlations between the rotational constants when calculating the r ρ m structure and the weighting scheme in the least-squares fits ( r ϵ , I and r 0 methods) are analyzed. The possibility of obtaining the true equilibrium CO distance from ab initio calculations is also discussed.

A simple and efficient procedure was developed for the synthesis of multisubstituted 2-aminothiophene derivatives. In the presence of catalytic amount of imidazole, ketones or aldehydes, dicyanomethane and elemental sulfur were converted into the corresponding 2-aminothiophene derivatives in moderate to high yields in DMF at 60 °C.

Potassium permanganate oxidizes a mixture of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (THP) 1 and dicyanomethane to 2-dicyanomethylidenetetrahydropyridine 2, but using manganese dioxide leads to the unusual oxidative hydroxymethylation of 1; subsequent treatment of the 3-hydroxymethyltetrahydropyridine 4 formed with aqueous potassium permanganate results in lactamination, accompanied by aromatization or oxodihydroxylation.

Ultrafast optical Kerr effect spectroscopy has been used to study the temperature-dependent orientational dynamics of 1,n-dicyano n-alkane liquids ranging from dicyanomethane to 1,8-dicyanooctane. The dependence of the reorientational times on temperature and viscosity is consistent with the molecules adopting a largely extended structure in the liquid state, with a preference for gauche conformations at the methylenes bonded to the cyanide groups. The data are also suggestive of temperature-dependent, collective structural rearrangements in these liquids.

Potassium permanganate oxidizes a mixture of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (THP) 1 and dicyanomethane to 2-dicyanomethylidenetetrahydropyridine 2, but using manganese dioxide leads to the unusual oxidative hydroxymethylation of 1; subsequent treatment of the 3-hydroxymethyltetrahydropyridine 4 formed with aqueous potassium permanganate results in lactamination, accompanied by aromatization or oxodihydroxylation.

3,5-Bis(trimethylsilyl)-1-methyl-4-thiophenoxypyridinium iodide reacts with the anion of malononitrile to give the corresponding dicyanomethylidene-1,4-dihydropyridine.[...]

A simple and efficient catalytic protocol for the 2-amino-5-substitutedselenophene-3-carbonitrile derivatives ( 4a – k ) via the one-pot condensation of dicyanomethane, selenium and various substituted esters using 1% cesium silica is reported. The present method offers several advantages such as high to excellent yields, short reaction times, recovery and reusability of catalyst, mild reaction conditions and easy workup procedures.