Protonation mediated interchange between mono- and bidentate coordination of N-benzoyl-N', N'-dialkylthioureas: Crystal structure of trans-bis(N-benzoyl-N', n'-di(n-butyl)thiourea-S)-diiodoplatinum(II)

Article abstract of DOI:10.1016/S0022-2860(97)00272-X

Treatment of a chloroform/ethanol solution of cis-bis(N-benzoyl-N; N'-di(n-butyl)thioureato-S,O)platinum(II) with an excess HI quantitatively converts the former cis complex into trans-bis(N-benzoyl-N; N'-di(n-butyl)thioureau-S)diiodoplatinum(II). The crystal structure of the latter complex is reported and represents the first example of a Pt(II) complex in which the amidic O-donor atom of the usually bidentate N-benzoyl-N; N'-di(butyl)thiourea ligand (HL) is pendant. In chloroform-d₃ solution, the trans-[Pt(HL-S)₂I₂] complex rapidly isomerizes to give a 1:4 mixture of the cis and trans isomers, as can be seen in the ¹H and ¹⁹⁵Pt NMR spectra.