Photoinduced deprotection of masked boronic acids enables light-triggered polycondensation of siloxanes

Various protecting groups have been developed for boronic acids, mostly based on diols. Alternatives include trifluoroborates and amine complexes, which offer easier synthesis and release under milder conditions. We present her a new strategy involving photocleavable protecting groups for boronic and borinic acids, based on the 2-nitrobenzyl motif. It enables controlled release of boronic acids, which were advantageously used in inducing reticulation in polymer matrices.