From 3,4-dinitrothiophene to nitrocyclopropanes and 1,1'-dinitro-1,1'-bi(cyclopropyl) compounds

Treatment of (E,E)-1,4-diaryl-2,3-dinitro-1,3-butadienes (I) with diazomethane in Et2O or THF represents a facile and high-yielding route to 2,2'-diaryl-1,1'-dinitro-1,1'-bi(cyclopropyl)s. The process exclusively produces diastereomeric mixts. of a chiral d,l pair and a meso form, the relative percentages of which depend on the aryl moiety, consistently with a concerted syn-stereoselective cyclopropanation of each double bond. With 1 mol-equiv of CH2N2, the cyclopropanation can effectively be limited to one double bond of the starting dinitrobutadiene, thus allowing a synthetically useful differentiation between the two originally conjugated nitrovinyl moieties. As verified with model derivs., the resulting vinylcyclopropanes can be cyclopropanated with excess diazomethane to give the same diastereomeric mixts. as obtained by direct bis(cyclopropanation) of I

7-Chloro-3,6-dimethyl-1H-indene-2-carbaldehyde

In the crystal structure of C12H11ClO, the (planar) molecules give rise to a parallel packing. A model crystal obtained by semi-empirical and packing-energy calculations is consistent with the observed structure

A novel potent non-nucleoside reverse transcriptase inhibitor acylthiocarbamate derivative with extensive intramolecular pi-pi interactions

In the crystal structure of the novel acylthiocarbamate derivative O-[2-(1,3-dioxo-2,3-dihydro-1H-isoindol-2-yl)-ethyl] N-(4-methylphenyl)-N-(3-nitrobenzoyl)thiocarbamate, C25H19N3O6S, intra- and intermolecular pi-pi interactions occur between the phthalimide and N-benzoyl moieties. The partial atomic charges, calculated by ab initio methods, are consistent with the observed structure

8-Chloro-6-phenyl-4H-[1,2,4]triazolo[4,3-a][1,5]benzodiazepin-5(6H)-one

The title compound, C16H11ClN4O, is an anticonvulsant agent. In the crystal, a particularly short C-H...N intermolecular hydrogen bond is noted [H...N 2.22 (2) \uc5]. The diazepine ring has a boat conformation

1,3-cycloaddition of benzonitrile oxides to diazepines. III. 1H-1,2-benzodiazepine

Arylnitrile oxide (1) and 1H-1,2-benzodiazepine(2) undergo 1,3-cycloaddition reactions to give derivatives of 1,2,4-oxadiazole (3) and isoxazole (4). Aithough usually stable, the nitrile oxide partly dimerizes giving a 1,2,4-oxadiazole (7). Secondary products were also identified: for one of the (6) the structure was unambiguously determined by X-ray diffraction. Overall kinetics and product distribution were measured at 40-70\ub0C, in mixtures of 1,1,2,2-tetrachloroethane and DMF: a set of parallel reactions was evidenced