Z,Z ISOMERS OF STERICALLY HINDERED 1,3-BIS(ARYL)-1,3-DIAZA-2-THIAALLENES, (ARN=)2S, IN THE CRYSTAL AND IN SOLUTION

It has been shown by X-ray structure analysis, H-1 NMR spectroscopy (i ncluding NOE) and PM3 calculations that symmetric isomers of the title compounds in the crystal and in solution have a Z,Z configuration sta bilized by n(N),pi interaction, but not the E,E configuration suggeste d earlier.