Sequential hydrothiolation-hydrosilylation: a route to the creation of new organosilicon compounds with preset structures

An efficient approach to the preparation of functional organosilicon compounds by sequential hydrothiolation (Ht) and hydrosilylation (Hs) reactions using commercially available catalysts (Karstedt's catalyst) and activators (UV alone or UV in the presence of benzophenone) is presented. Structure–reactivity relationships for Si–H containing silanes with the sulfide bond in different positions (α, β, and γ, and via a siloxane spacer) were firstly demonstrated. This approach has been tested on disiloxane and then successfully applied for the modification of a cis-stereoregular silsesquioxane ring containing 4 vinyl and 4 hydrido groups. Also we demonstrated the efficiency of introducing alkoxy groups into a vinyl–hydride-containing disiloxane at both the Ht and Hs stages. Thus, the approach that we developed is a convenient and promising tool for the synthesis of complex organosilicon molecular ensembles with an unlimited variety of structures and substituents.