Genuine low tonnage technologies of isocyanate and ureido silanes, and their derivatives with carboxylic group, based on 3-chloropropylotrimetoxysilane as the raw material, are presented. Silanes are necessary as auxiliary agents in several branches of chemical and rubber industries as well as in foundries. Starting the production of those compounds will make possible the development of a new polish speciality - low tonnage production of organofunctional silanes.