Mihaela Cristea

Synthesis and X-ray Structure of a New Pyrrolo(1,2-b)- pyridazine Derivative

The synthesis, characterization and X-ray crystal structure of 2-(4-chloro-phenyl)-7-methylpyrrolo[1,2-b]pyridazine are reported. The compound crystallizes in the space group P21/c (No.14) with a =3.8568(1), b = 11.0690(3), c = 26.4243(7) Å, β = 92.777(1)° and Z = 4. Accurate molecular parameters for the novel heterocyclic system were obtained from intensity data collected at 113K. The molecule assumes a planar conformation in the crystal and the packing is based on π-π stacking with interplanar spacing 3.400 Å, typical of aromatic molecules with potential for displaying useful optical properties.

1-Phenylselanylazulenes: synthesis and selenium atom oxidation

The phenylselanylation of azulene with PhSeCl or PhSeBr was reported. Clean electrophilic substitution of azulene in positions 1 and/or 3 occurred with the first reagent whereas with PhSeBr a complex mixture of products was generated suggesting a radicalic mechanism. The influence on the reaction route of the substituent attached at position 1 of azulene, or of the alkyl positions in alkylated azulenes was investigated. 1-Phenylselanylazulene and 1,3-bis(phenylselanyl)azulene were oxidized using sodium metaperiodate. The oxidation took place at selenium atom and afforded azulenes substituted with PhSe(O) and/or PhSe(O2) groups in positions 1 and/or 3. The magnetic and electronic spectra as well as the electrochemical oxidation and reduction potentials of the obtained products were recorded and the results were briefly discussed.Graphical abstract.