The aza-Michael reaction as an alternative strategy to generate advanced silicon-based (macro)molecules and materials

Aza-Michael reaction is a simple and accessible addition reaction performed at moderate temperature, possibly without a catalyst and without releasing by-products. Its versatility allows designing specific structures thanks to the availability of a multitude of Michael acceptors and Michael donors. The reaction rate of the aza-Michael reaction can be improved by adding different co-reactants (polar protic solvents, catalysts) and/or adjusting the external energy sources (e.g. moderate to high temperatures or high pressures). Here, we show that this addition reaction is efficient for modifying or curing silicon containing molecules, oligomers and polymers. The pros and cons of applying the aza-Michael reaction to silicon-containing molecules (including alkoxysilanes and PDMS) are highlighted. A large variety of intermediates such as coupling agents, reactive diluents, and sol-gel precursors prepared by the azaMichael reaction are presented. Finally, applications of these, including products ranging from functional silicone intermediates to soft (unfilled) elastomers, are reported. (C) 2017 Elsevier B.V. All rights reserved.