The first series of mononuclear thiomolybdenyl complexes, Tp(.)Mo(V)SX(2) [
Tp* = hydrotris(3,5-dimethylpyrazol-1-yl)borate, X/X-2 = anion/dianion], ha
s been prepared. The complexes, which have been characterized by analytical
, mass spectrometric, spectroscopic and X-ray crystallographic studies, pro
vide insights into the electronic nature and chemistry of the catalytically
and biologically important thiomolybdenyl unit.