organometallic monoacyl alkylphosphines, processes for their preparation, photocurable composition, process for photopolymerization of said compounds, use of said composition, coated substrate as well as process for photographic production of relief images.
Compounds of the formula I in which Ar is a group or unsubstituted or substituted cyclopentyl, cyclohexyl, naphthyl, biphenylyl or an O-, S- or N-containing 5- or 6-membered heterocyclic ring； R<；SUB>；1 <；/SUB>；and R<；SUB>；2 <；/SUB>；are C<；SUB>；1<；/SUB>；-C<；SUB>；20<；/SUB>；alkyl, OR<；SUB>；11<；/SUB>；, CF<；SUB>；3 <；/SUB>；or halogen； R<；SUB>；3<；/SUB>；, R<；SUB>；4 <；/SUB>；and R<；SUB>；5 <；/SUB>；are hydrogen, C<；SUB>；1<；/SUB>；-C<；SUB>；20<；/SUB>；alkyl, OR<；SUB>；11 <；/SUB>；or halogen； R<；SUB>；6 <；/SUB>；is unsubstituted or substituted C<；SUB>；1<；/SUB>；-C<；SUB>；24<；/SUB>；alkyl, C<；SUB>；2<；/SUB>；-C<；SUB>；24<；/SUB>；alkyl, which is interrupted by O, S or NR<；SUB>；14 <；/SUB>；and is unsubstituted or substituted； C<；SUB>；2<；/SUB>；-C<；SUB>；24<；/SUB>；alkenyl, uninterrupted or interrupted by O, S or NR<；SUB>；14 <；/SUB>；and unsubstituted or substituted； unsubstituted or substituted C<；SUB>；7<；/SUB>；-C<；SUB>；24<；/SUB>；arylalkyl； C<；SUB>；4<；/SUB>；-C<；SUB>；24<；/SUB>；cycloalkyl, uninterrupted or interrupted by O, S and/or NR<；SUB>；14<；/SUB>；； or C<；SUB>；8<；/SUB>；-C<；SUB>；24<；/SUB>；arylcycloalkyl； R<；SUB>；11 <；/SUB>；is C<；SUB>；1<；/SUB>；-C<；SUB>；20<；/SUB>；alkyl, C<；SUB>；3<；/SUB>；-C<；SUB>；8<；/SUB>；cycloalkyl, phenyl, benzyl or C<；SUB>；2<；/SUB>；-C<；SUB>；20<；/SUB>；alkyl, interrupted by O or S and unsubstituted or substituted； R<；SUB>；12 <；/SUB>；and R<；SUB>；13 <；/SUB>；are hydrogen, C<；SUB>；1<；/SUB>；-C<；SUB>；20<；/SUB>；alkyl, C<；SUB>；3<；/SUB>；-C<；SUB>；8<；/SUB>；cycloalkyl, phenyl, benzyl or C<；SUB>；2<；/SUB>；-C<；SUB>；20<；/SUB>；alkyl, interrupted by O atoms and unsubstituted or substituted； or R<；SUB>；12 <；/SUB>；and R<；SUB>；13 <；/SUB>；together are C
