L. Heinrich et al., Synthesis of polydentate ligands containing amides and thiols for biomimetic metal complexes, SYN COMMUN, 31(9), 2001, pp. 1323-1333
Three pentadentate "N2S3'' and one tetradentate "N2S2" new ligands with "N"
= CONH and "S" = SH have been synthesized. The key step is the direct diam
ide formation from the malonyl diester and the amines in the presence of tr
imethylaluminum.