β‐Donor Bonds in Compounds Containing SiON Fragments

Strongly compressed Si-O-N angles are observed in H3SiONMe2 (crystal structure shown on the right) and H2Si(ONMe2)2 with respect to the Si-O-C angle in isoelectronic SiOC compounds. This is due to weak donor–acceptor bonds between the Si and N atoms. The resulting partial hypercoordination at silicon explains the unique chemical behavior of hydroxylaminosilanes.