IR and NMR studies of symmetrically and unsymmetrically bonded N,N‐dialkyldithiocarbamates

In order to find characteristic differences between symmetrically and unsymmetrically bonded N,N‐dialkyldithiocarbamates, their IR and 1H NMR spectra have been examined. The IR data firmly underline a previously reported infrared criterion which makes it possible to distinguish the two types of bonding. In the spectra of the unsymmetrical N,N‐diethyldithiocarbamates a band at 1000 cm−1 is assigned to the CS stretching mode. Although the rotation around the S2C‐NR2, bond in several dithiocarbamato complexes will be strongly hindered at low temperatures, no splitting of the NMR signals of the N‐alkyl groups could be observed. This may be attributed to an extremely small difference in magnetic environment of the N‐alkyl moieties in the rotamers.