Reactions of hafnium(IV) isopropoxide-isopropanol (1/1) with 2-aminocyclopent-1-ene-1-dithiocarboxylic acid and itsN-alkyl derivatives

A series of hafnium(IV) complexes has been synthesised by the reaction of hafnium(IV) isopropoxide-isopropanol(1/1) with 2-aminocyclopent-1-ene-1-dithiocarboxylic acids RNHC(CH2)3CC(S)SH, (where R=H, Me, Et or Bu) in 1∶1 and 1 ∶ 2 molar ratios. The compounds have been characterized by elemental analysis, i.r. and1H n.m.r. spectral studies. The complexes polymerise slowly in solution, probablyvia the sulphur atom of the >C=S group.