Stereoselective syntheses of alkyl Z-2-(2-amino-4-oxo-1,3-selenazol-5(4H)- ylidene)acetates in solvent-free conditions, X-ray single crystal structure analysis of ethyl Z-2-(2-amino-4-oxo-1,3-selenazol-5(4H)-ylidene)acetate

Abstract

Selenourea reacts with dialkyl acetylenedicarboxylates under solvent-free conditions to form 1:1 adducts, which undergo a cyclization reaction to produce alkyl Z-2-(2-amino-4-oxo-1,3-selenazol-5(4H)-ylidene)acetates, in good yields. The stereochemistry of the ethyl Z-2-(2-amino-4-oxo-1,3-selenazol-5(4H)-ylidene) acetate was established by X-ray single crystal structure analysis. The reaction is completely stereoselective. © 2005 Verlag der Zeitschrift für Naturforschung.