Heavy Neutral and Anionic Pnictogen Thiocyanates.

Area of Science:

• Inorganic Chemistry
• Organometallic Chemistry
• Materials Science

Background:

• Thiocyanate (SCN) ligands are versatile building blocks in coordination chemistry.
• The synthesis and characterization of heavy metal complexes with diverse coordination environments remain an active area of research.
• Understanding the coordination modes of SCN ligands is crucial for designing new materials.

Purpose of the Study:

• To synthesize and characterize novel diisothiocyanate salts and heavy metal thiocyanate complexes.
• To investigate the structural diversity and coordination behavior of antimony and bismuth thiocyanates.
• To explore the reactivity of [PPN]SCN with various metal fluorides and trimethylsilyl isothiocyanate.

Main Methods:

• Reaction of [PPN]SCN with Me3Si-SCN to form [PPN][H(NCS)2].
• Reaction of EF3 (E = Sb, Bi) with Me3Si-SCN to yield E(NCS)3 species.
• Crystallization and single-crystal X-ray diffraction analysis of synthesized compounds.

Main Results:

• Isolation and characterization of [PPN][H(NCS)2] and heavy metal thiocyanates E(NCS)3 (E = Sb, Bi).
• Synthesis of [PPN]2[Sb(NCS)5] and [PPN]2[Bi(NCS)3(SCN)2·THF] complexes.
• Structural determination revealed diverse coordination geometries including trigonal-pyramidal, square-pyramidal, distorted pentagonal-bipyramidal, and octahedral environments for Sb and Bi centers.

Conclusions:

• The study successfully synthesized and structurally elucidated a range of novel thiocyanate compounds.
• The coordination behavior of SCN ligands in antimony and bismuth complexes is highly varied, influenced by metal, stoichiometry, and crystallization solvent.
• The findings contribute to the understanding of heavy metal thiocyanate chemistry and coordination modes.