58549-95-4Relevant academic research and scientific papers
(2,6)- and (2,5)Pyrazinophanes: Synthesis and Molecular Structure
Eiermann, Uwe,Krieger, Claus,Neugebauer, Franz A.,Staab, Heinz A.
, p. 523 - 533 (2007/10/02)
The title compounds 1-3 and their methyl derivatives 4-7 were synthesized either by photolytic sulfur extrusion from the corresponding 2,11-dithiapyrazinophanes 24-26 or by Hofmann 1,6-elimination of the appropriate trimethylammonium hydroxides followed by dimerization of the generated 2,5-dihydro-2,5-dimethylene-pyrazines. α-Chlorination of the methylpyrazines 8-10 with N-chlorosuccinimide gave the required precursors 11, 12, 14, 17, and 18.The results of the X-ray structure determinations for 1-4 and 7 which indicate an unequivocal isomer assignment are discussed with regard to steric strain in these molecules.The electronic spectra of the pyrazinophanes 1-7 are reported and compared with those of the parent methylpyrazines.
