Qualitative classification of dithiocarbamate compounds from 13c-n.m.r. and i.r. spectroscopic data by pattern recognition techniques

Abstract

Unsupervised pattern recognition permits qualitative classification of N, N-dialkyldithio-carbamate complexes into five classes, denoted as free ligands, complexes of main group elements, and complexes of transition metals both with FON = 0.5 or FON > 0.5. Within the transition metal complexes, metals with electron configuration d 6 or d 8 and d 0 or d 10 can be further distinguished. The class of main group elements is subdivided into organic dithiocarbamates including PE 3 and TeE 2 (E = Et 2DTC) and a subclass of main group element complexes. Supervised techniques based on these five classes show that the descriptors σ(N 13CS 2), v(CXXXN) 1 and atom number are dominant in classifying compounds. The substituent descriptor and σ(α- 13CH 2) are less important. The classification and ranking of the descriptor quality gives an insight into the relationship between the quantities measured. Classifications which disagree with chemical expectations are readily identified and this improves understanding of the chemical background.