The o-isopropyl and n-ethyl thionocarbamates can be modified by substitution
of an alkoxy carbonyl group on the N donors.
This modification provides additional active donor oxygen in the form of C=O attached
to the alkoxy group. Functional groups of this kind are not restricted to thionocarbamates.
They are much more complex groups [O–C–(=O)—NH–C(=S)–O] with different
properties. The increased electron density on the C=O portion into which density
is equally divided allows for the participation of oxygen in bonding with mineral
surfaces.
These reactions are unique since they are conducted in an aqueous medium and there are
no sulfur-containing by-products.
