Structural Diversity in a Family of Copper(I) Thioether Complexes

Copper(I) complexes of the tridentate thioether ligands [PhB(CH2SCH3)3] (abbreviated PhTt), [PhB(CH2SPh)3]
(PhTtPh), [PhB(CH2StBu)3] (PhTttBu), and [PhB(CH2SpTol)3] (PhTtpTol) and bidentate thioether ligands [Ph2B(CH2SCH3)2] (Ph2Bt), [Et2B(CH2SCH3)2] (Et2Bt), and [Ph2B(CH2SPh)2] (Ph2BtPh) have been prepared and characterized.
The solution and solid state structures are highly sensitive to the identity of the borato ligand employed. Ligands
possessing the smaller (methylthio)methyl donors, [PhTt] and [Ph2Bt], yielded tetrameric species, [(PhTt)Cu]4
and [(Ph2Bt)Cu]4, containing both terminal and bridging thioether ligation. The ligands containing the larger
(arylthio)methyl groups, [PhTtPh] and [PhTtpTol], form monomeric [PhTtAr]Cu(NCCH3) in solution and one-dimensional extended structures in the solid state. Each complex type reacted cleanly with acetonitrile, pyridine,
or triphenylphosphine generating the corresponding four-coordinate monomer, of which [PhTtPh]Cu(PPh3),
[PhTtpTol]Cu(PPh3), and [Et2Bt]Cu(PPh3)2 have been structurally characterized.