Photoreactive compounds

A compound comprising a terminal group of formula (Ia)

• wherein:
• the doted line means a linkage of the terminal group to the residue of the compound;
• A1 and A2 each independently are a ring system of 5 to 40 atoms, wherein each ring system includes at least one unsaturation directly connected via electron conjugation (□-□ bonding) to the double bond shown in formula (I);
• and wherein A2 is linked to a polymerizable group by a single bond or at least one spacer unit;
• R1 is hydrogen, a substituent L or a straight-chain or branched, substituted or unsubstituted C1-C12alkyl, in which one or more C-atom, CH— or CH2— group is unreplaced or replaced by a linking group;
• and wherein if
• W is hydrogen and Z is an electron withdrawing group, then
• R4, R5 are hydrogen, and R2 and R3 are independently from each other an electron-donating single substituent, preferably these electron-donating single substituents are in meta-position to each other;
• or
• R2 and R3 form together the residue of an electron-donating ring which is condensed to ring A1;
• or
• if W is hydrogen and Z is an electron withdrawing group, then
• R4, R5 are independently from each other hydrogen, a substituent L, or an electron-donating single substituent, with the proviso that at least one R4 or R5 is a substituent L, or an electron-donating single substituent;
• or R4, R5 form together the residue of an electron-donating ring which is condensed to ring A2;
• and,
• R2 and R3 form together the residue of an electron-donating ring which is condensed to ring A1;
• or
• R4 is —O—C2-C6alkyl, such as —O-ethyl, —O-propyl, —O-butyl, —O-pentyl, —O-hexyl, R5 is hydrogen and R2 and R3 are hydrogen or an electron-donating single substituent, preferably both R2 and R3 are an electron-donating single substituent;
• or
• R4, R5 are independently from each other a substituent L, an electron-donating single substituent, or hydrogen;
• and R2 and R3 are independently from each other —O—C2-C6alkyl, such as —O-ethyl, —O-propyl, —O-isopropyl, —O-butyl, —O-tert-butyl, —O-sec-butyl, —O-pentyl, —O-isopentyl, —O-hexyl;
• or
• R4, R5 are independently from each other a —O—C2-C6alkyl, such as —O-ethyl, —O-propyl, —O-isopropyl, —O-butyl, —O-tert-butyl, —O-sec-butyl, —O-pentyl, —O-isopentyl, —O-hexyl or hydrogen, and R2 and R3 are independently from each other —O—C2-C6alkyl, such as —O-ethyl, —O-propyl, —O-isopropyl, —O-butyl, —O-tert-butyl, —O-sec-butyl,
• —O-pentyl, —O-isopentyl, —O-hexyl;
• or
• R4, R5 are independently from each other a substituent L, an electron-donating single substituent, preferably R4, R5 are O—C1-C6alkyl, more preferably —O-methyl, —O-ethyl, and R2 and R3 are independently from each other —O—C1-C6alkyl, such as —O-methyl,
• —O-ethyl, —O-propyl, —O-isopropyl, —O-butyl, —O-tert-butyl, —O-sec-butyl, —O-pentyl, —O-isopentyl, —O-hexyl;
• or if W is an electron withdrawing group and Z is hydrogen, then
• R4, R5 are independently from each other hydrogen, a substituent L, an electron-donating single substituent, or R4, R5 form together the residue of an electron-donating ring which is condensed to ring A2 or hydrogen, and R2 and R3 are independently from each other an electron-donating single substituent, or form together the residue of an electron-donating ring which is condensed to ring A1;
• most preferred is
• W is hydrogen and Z is an electron withdrawing group, then
• R4, R5 are hydrogen, and R2 and R3 are independently from each other an electron-donating single substituent, preferably these electron-donating single substituents are in meta-position to each other;
• or
• R2 and R3 form together the residue of an electron-donating ring which is condensed to ring A1;
• or
• if W is hydrogen and Z is an electron withdrawing group, then
• R4, R5 are independently from each other hydrogen, a substituent L, or an electron-donating single substituent, with the proviso that at least one R4 or R5 is a substituent L, or an electron-donating single substituent;
• or R4, R5 form together the residue of an electron-donating ring which is condensed to ring A2;
• and,
• R2 and R3 form together the residue of an electron-donating ring which is condensed to ring A1;
• or
• or if W is an electron withdrawing group and Z is hydrogen, then
• R4, R5 are independently from each other hydrogen, a substituent L, an electron-donating single substituent, or R4, R5 form together the residue of an electron-donating ring which is condensed to ring A2 or hydrogen, and R2 and R3 are independently from each other an electron-donating single substituent, or form together the residue of an electron-donating ring which is condensed to ring A1.