Reactions of N- and S-substituted thiosemicarbazones with Cu(I) have been examined. No complexes are formed when the S atom is substituted and(or) when the N2 hydrogen atom is replaced by Me. 4,4-Dimethyl derivatives not only give the usual 1:1 complexes, but also 2:1 complexes (2 thiosemicarbazones to 1 copper) in which copper has been oxidized to Cu(II). Reactions of thiosemicarbazones with Cu(II) give 1:1, 2:1, and probably a mixture which corresponds to 2:3 complexes. A discussion on the possible structures for the 1:1 complexes is given and they are best represented as polymers, the metal being bonded to the sulphur and to a nitrogen atom of the thioseraicarbazide portion of the molecule. Infrared spectra of these compounds have been examined, particularly in the 1100 cm−1 region where a strong to medium band disappears in going from thiosemicarbazones to copper complexes. It is suggested that this band is due to the C=S vibration.
The synthesis of new 1,2,4,3-triazaphospholes is described: a number of 5-methylthio 1,2,4,3-triazaphospholes, substituted in the 1, 2, or 4 position. The 1,5-disubstituted compound 6 is stable, whereas 2,5-disubstituted compounds 14 and 16 undergo an equilibrium with their tetrameric form, the cyclotetraphosphazanes [14]4 and [16]4. 5-Methylthio 4-alkyl 1,2,4,3-triazaphospholes exist only in the tetrameric forms [12]4 and [13]4. [12]4 can be depolymerized by complexation with a Lewis acid, giving the complexed triazaphosphole 12•BF3. The 15N NMR spectrum of compound 16, the N-silylated derivative of 15, allows us to confirm the position of the trimethylsilyl group. MNDO calculations are in good agreement with experimental results, such as the reaction of 1,4-diazadienes with triazaphospholes providing new tetracoordinated phosphorus spirocompounds 21–25.