R-alkoxysilanes are the monomer workhorses of silicon-based sol-gel chemistry and are used as the building blocks for materials from silicas to silicones. However, uncontrolled hydrolysis, premature condensation and overall polymerization control have plagued the sol-gel and siloxanes communities since their inception. This study is to develop new silicon sol-gel chemistry methodologies that utilize photo protecting groups (PPGs) with R-alkoxysilanes to control the synthesis of unique (i.e. sequence defined) siloxanes for use in a variety of applications, including sequence defined siloxane polymers, resins, porous materials, photo-healable polymers, 3D printed scaffolds, and photo-controlled surface functionalization in coatings (i.e. interlayer dielectrics). We have undertaked a fundamental study of the synthesis and characterization of alkoxysilanes with bulky PPGs (2-Nitrobenzyloxy, dimethylaminobenzyls, phenacyls, BODIPYs, and methylnitrobenzyls). These bulky photoreactive alkoxysilanes will give added hydrolytic stability, can be removed on demand using light, and make it possible to functionalize the R-groups with unusual substituents. The added stability also allows for column purification, which is difficult for non-bulky alkoxysilanes. To start this marathon, a series of 2-nitrobenzyloxy alkoxysilanes have been synthesized with varying functionalities (R<sub>x</sub>-(alkoxy)<sub>y</sub>silanes, with x=0-3 and y=1-4) by newly developed methods.

Photocaged R-alkoxysilanes for on-demand functionalization and polymerization control

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.