Synthesis and characterization of pyrimidyl- and pyrazinylselenium compounds: X-ray structure of 2,5-bis(methylselenenyl)pyrazine

Abstract

A methodology for the lithiation of pyrimidine (1a) was developed and used for the synthesis of pyrimidylselenium compounds. The procedure involved prior complexation of 1a with 2.2 equiv. of BF3 center dot Et2O followed by a reaction with LDA or LTMP. The pyrazinylselenium derivatives were synthesized from the direct lithiation of pyrazine (1b) as the BF3-directed lithiation failed to give the desired products. All the synthesized compounds were characterized by elemental analysis, NMR (H-1 and C-13) and Mass spectroscopy. In addition, 2,5-bis(methylselenenyl)pyrazine (9b) was characterized by single crystal X-ray crystallography. (C) 2014 Elsevier B.V. All rights reserved.