The reaction of the sodium salt of pyrrole with N,N-dimethylthiocarbamoyl chloride in N,N-dimethylformamide gave N,N-dimethylpyrrole-1-carbothioamide (Hnpt), while the reaction of pyrrole with N,N-dimethylthiocarbamoyl chloride under phase transfer conditions afforded N,N-dimethylpyrrole-2-carbothioamide (Hapt), together with a very small amount of N,N,N′,N′-tetramethylpyrrole-1,2-dicarbothioamide. Hnpt and Hapt were metallated with lithium tetrachloropalladate in methanol to yield PdCl(npt) and PdCl(apt), respectively. Both complexes reacted with tri-n-butylphosphine (PBu3) and 4-tert-butyl-pyridine (tbp), forming PdCl(npt)(PBu3), PdCl(npt)(tbp), PdCl(apt)(PBu3) and PdCl(apt)(tbp). These and some additional complexes were characterized spectroscopically. In the npt complexes, the ligand was cyclopalladated at C(2) of the pyrrole ring, forming a five-membered, organometallic chelate ring accompanied by thioamide sulphur coordination. In the apt complexes, the ligand acted as a bidentate NS chelate, the ring NH proton being deprotonated. The X-ray analysis of PdCl(npt)(PBu3) and PdCl(apt)(PBu3) confirmed the coordination modes.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry