Organometallic complexes
View Patent ↗Organometallic complexes comprising a trivalent lanthanide metal ion complexed with one or more polydentate ligands containing one or more pyrazolyl-derived groups, such as trispyrazolyl borate species, are useful in light emitting materials e.g., in electroluminescent flat panel displays. In the complexes, several classes of which are novel, a coordinate bond is formed between the metal and one of the nitrogen atoms of the pyrazolyl rings.
1. An organometallic complex having the formula (I):
[(Z(L) 3 ) p M]A q (I)
wherein Z is a carbon atom or R 1 (B)— fragment;
p is 1,2 or 3;
q is 3-p;
A is a counterion;
R 1 is: (i) hydrogen, aryl or aralkyl each optionally substituted with from one to five halogen or C 1 to C 6 alkyl groups; or (ii) C 1 to C 6 alkyl, C 1 to C 6 alkenyl or C 1 to C 6 alkynyl each optionally substituted with one or more halogen atoms;
each L is covalently bound to Z and is independently selected from a group of the formula (II) or (III)
wherein R 2 and R 3 are independently selected from:
(i) halogen, cyano, nitro, sulphono, amino, C 1 to C 6 alkylamino, C 1 to C 6 alkylamido, carboxyl, C 1 to C 6 alkyloxycarbonyl, hydroxy, C 1 to C 6 alkoxy, C 1 to C 6 alkylcarbonyloxy, C 1 to C 6 alkylcarbonyl, C 1 to C 6 haloalkoxy;
(ii) aryl or aralkyl each optionally substituted on the aryl ring or, for aralkyl, on the alkylene chain with from one or more of the groups mentioned under (i) above; and
(iii) C 1 to C 6 alkenyl or C 1 to C 6 alkynyl each optionally substituted with one or more of the groups mentioned under (i) and (ii) above;
R 2 is —(CX 2 ) n X wherein n is 0 or a positive integer from 1 to 6 and X is halogen; or
R 2 and R 3 are linked so as to form a fused aromatic or non-aromatic ring system with the pyrazolyl ring of L; and
R 4 is trifluoromethyl; and
M is a trivalent lanthanide metal ion.
2. An organometallic complex having the formula (I):
[(Z(L) 3 ) p M]A q (I)
wherein Z is a carbon atom or R 1 (B)— fragment;
p is 1, 2 or 3;
q is 3-p and;
A is a counterion;
R 1 is: (i) hydrogen, aryl or aralkyl each optionally substituted with from one to five halogen or C 1 to C 6 alkyl groups; or (ii) C 1 to C6 alkyl, C1 to C 6 alkenyl or C 1 to C 6 alkynyl each optionally substituted with one or more halogen atoms;
each L is covalently bound to Z and is independently selected from a group of the formula (II) or (III)
wherein R 2 is trifluromethyl;
R 3 is hydrogen; and
R 4 is —(CX 2 ) n X wherein n is 0 or a positive integer from 1 to 6 and X is halogen; or orthodihalogenated or orthodiperhalomethylated aryl, optionally further substituted on the aryl ring; and
M is a trivalent lanthanide metal ion.
3. An organometallic complex having the formula (I):
[(Z(L) 3 ) p M]A q (I)
wherein Z is an R 1 (B)— fragment;
p is 1, 2 or 3;
q is 3-p and;
A is a chloride ion;
R 1 is hydrogen;
each L has the formula (II) and is covalently bound to Z;
wherein R 2 is —CF 3 ;
R 3 is H; and
R 4 is —CF 3 ; and
M is Eu.