Kaya, Afşin A.; Salamci, Emine; Menzek, Abdullah; Erdem, Safiye S.; Şahin, Ertan; Ecer, Kadriye

Reaction of (1S*,7R*)-9-oxabicyclo[4.2.1]non-7-en-1-ol (5) with dimethyl 1,2,4,5-tetrazine-3,6-dicarboxylate (6) produced (2R*,4R*)-dimethyl 4-(7-oxooxepan-2-yl)-1,4-dihydropyridazine-3,6-dicarboxylate (11) in a one-pot reaction involving cycloaddition at ambient conditions. The structure of the rearrangement product 11 was determined by X-ray crystallographic analysis. Its formation was discussed based on experimental studies and density functional theory calculations. The driving force of this unusually facile reaction was the stability of the caprolactone product 11 and the extremely exorgenic loss of N2. Structural factors facilitating this rearrangement were also explored employing PCM//M06-2X/6-31G(d, p) calculations.

Kaya, Afşin Ahmet; Menzek, Abdullah; Şahin, Ertan

Brominations of mono addition products of 1,4-cyclohexadiene with 2,4-dinitrobenzenesulfenyl chloride (RSCl) selectively gave 1R(S),2R(S),4R(S), 5R(S)-4,5-dibromo-2-(2,4-dinitrophenylthio)cyclohexyl acetate and 1R(S),2R(S),4R(S),5R(S)-4,5-dibromo-2-chlorocyclohexyl)(2,4-dinitrophenylthio) sulfane. From series reactions 7-oxabicyclo[4.1.0]hept-3-ene with reagents, such as RSCl, NaN3, and H2SO4/Ac2O, six 1,2,4,5-tetrasubstituted cyclohexane derivatives including S, O, N, Cl, and Br were selectively obtained. Formations and structures of the products were discussed.

Kaya, Afşin Ahmet; Şengül, Mehmet Emin; Menzek, Abdullah; Kayaardi, Ibrahim; Karakuş, Murat; Şahin, Ertan

Each adduct of α-terpinene with p-quinone and 1,4-naphthoquinone in Ac2O/Et3N at 180 °C gives two aromatic products, one of which had a distinctive smell formed by the loss of an ethylene group. Here, we report the crystal structure of (1RS, 4RS)-1-isopropyl-4-methyl-1,4-dihydro- 1,4-ethanoanthracene-9,10-diyl diacetate. It is crystallised in an orthorhombic space group, Pbca, with cell dimensions a = 10.2899(7), b = 19.7804(9), c = 19.7519(8) Å and Z = 8. According to its NMR and X-ray diffraction data, the isopropyl and acetate groups slowly rotate.