Investigations on Structure and Transformation of Some Organometallic Compounds in Solution

Earlier NMR investigations revealed that the tetrameric [Me3SnL]4 compound [Me=methyl group, CH3; L=cupferronato anion, PhN2(O)O-] falls apart to monomeric units in chloroform solution. Comparison of Moessbauer spectra of the crystalline and the dissolved form indicated a minor change in structure, but not clearly. From the four possible structures in solution, two could be excluded by the help of partial quadrupole splitting (PQS) model calculations. The final decision between the remaining two possible monomeric structures was made by IR spectroscopy. The authors cite and, using PQS calculations, explain the case of another compound, [Me2N(CH2)3]2SnF2, the two structural isomers of which had been found to have very similar spectra in spite of a seemingly great difference between the positions of the ligands.