The imidyl compounds, according to the invention, of the formula I are suitable for the manufacture of polymers which can be crosslinked by light, which polymers can be, for example, polyesters, polyamides, polyamide-imides, polyimides, polyester-polyamides, polyester-amide-imides, polyethers, polyamines, polysaccharides and polysiloxanes. Polymers of this type are suitable for carrying out photochemical processes. Compared with known polymers, the polymers based on the imidyl compounds according to the invention have the advantage that they are photochemically substantially more sensitive. In addition, this sensitivity can also be further increased effectively by a combination with sensitizers.