Title: Functionalized metal complexes
Abstract: Described herein are metal complexes having the formula ##STR1##
wherein M is nickel, palladium, or platinum; Q1-Q4 are each independently sulfur, selenium, or tellurium; X1-X4 are each independently a divalent linking group having 1 to about 125 carbons; m1 to m4 are each independently 0 or 1; and W1-W4 are each independently hydrogen, carboxylic acid, carboxylic acid anhydride, carboxylic acid chloride, sulfonic acid, or sulfonyl chloride, with the proviso that W1-W4 are not all hydrogen. The complexes have strong absorptions in the near infrared.
Patent Number: 6,933,399 Issued on 08/23/2005 to Mueller-Westerhoff, et al.
| Inventors:
|
Mueller-Westerhoff; Ulrich T. (Storrs, CT);
Sanders; Richard W. (Lisbon, CT)
|
| Assignee:
|
The University of Connecticut (Storrs, CT)
|
| Appl. No.:
|
429206 |
| Filed:
|
May 2, 2003 |
| Current U.S. Class: |
556/28; 556/136; 556/146 |
| Intern'l Class: |
C07F 017/02; C07F 019//00; C07F 015//00 |
| Field of Search: |
556/28,136,146
|
References Cited [Referenced By]
U.S. Patent Documents
Other References
Crowley, J.I. et al. "Polymeric Films as Materials for Ablation-Type Holeburning
with IR Lasers." IBM Technical Disclosure Bulletin. Apr., 1982. vol. 24, No. 11B,
p. 6186.
Drexhage, K.H. and Muller-Westerhoff, U.T. "New Q-Switch Compounds for Infrared
Lasers," IEEE Journal of Quantum Electronics. Sep., 1972. vol. QE-8, No. 9, p. 759.
Grimaldi, John J. and Lehn, Jean-Marie. "Multicarrier Transport: Coupled Transport
of Electrons and Metal Cations Mediated by an Electron Carrier and a Selective
Cation Carrier." Journal of the American Chemical Society. Feb. 28, 1979. pp. 1333-1334.
Herman, Zelek S. et al. Electronic Spectra and Structure of Bis(ethylene-1,2-dithiolato)nickel
and Bis(propene-3-thione-1-thiolato)nickel. Inorganic Chemistry. 1982. vol. 21,
No. 1, pp. 46-56.
Mueller-Westerhoff, Ulrich T. and Alscher, Arnold. "Transition-Metal Complexes
of Malonaldehyde and Dithiomalonaldehyde." Angew. Chemical International Edition
English. 1980. vol. 19, No. 8, pp. 639-639.
Mueller-Westerhoff, Ulrich T. and Vance, Blake. "Dithiolenes and Related Species."
Comprehensive Coordination Chemistry: The Synthesis, Reactions, Properties & Applications
of Coordination Compounds. 1987. Pergamon Press. pp. 595-631.
Mueller-Westerhoff, Ulrich T. et al. "The Synthesis of Dithiolene Dyes with Strong
Near-IR Absorption." Tetrahedron. 1991. vol. 47, No. 6, pp. 909-932.
Mueller-Westerhoff, U.T. et al. "Near-IR Dyes for the 1.3 to 1.5 Micron Region:
The Use of Substituted Dithiolene Complexes." Mol. Cryst. Leq. Cryst. 1990. vol.
183, pp. 291-302.
Nazzal, Adel and Mueller-Westerhoff, Ulrich T. "Cyclic Electron Delocalization
in Transition Metal Complexes with Sulfur-Containing Conjugated Ligands." Transition
Met. Chem. 1980. No. 5, pp. 318-320.
Ohki, Akira et al. "Ion Transport Through Liquid Membrane Driven by Redox Potential
Multi-Component Ion Carrier as a Mediator." The Chemical Society of Japan: Chemistry
Letters.1980. pp. 1591-1594.
Sanders, Richard West Jr. "Synthesis and Inventigation of Square Planar Bis(ferrocenyl)
Dithiolene Complexes of Nickel, Palladium, and Platinum: Control of Near-Infrared
Absorption and Other Properties by Ligand Modification." Dissertation, University
of Connecticut. 2002. pp. 1-119.
Schrauzer, Dr. G.N. et al. "Bis-dithionkemplexe von Ubergangsmetallen." Angew.
Chemical. 1964. vol. 76, No. 8, p. 345.
Underhill, A.E. et al. "Developments in the Chemistry of Sulphur-Donor Ligands."
Elsevier Science: Synthetic Metals. 1995. vol. 70, pp. 1101-1104.
|
Primary Examiner: Nazario-Gonzalez; Porfirio
Attorney, Agent or Firm: Cantor Colburn LLP
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority from Provisional Application Ser. No. 60/378,179,
filed May 2, 2002, which is incorporated herein by reference in its entirety.
Claims
1. A composition comprising a metal complex having the formula
##STR21##
wherein
M is nickel, palladium, or platinum;
Q
1-Q
4 are each independently sulfur, selenium, or tellurium;
X
1-X
4 are each independently a divalent linking group having
1 to about 125 carbons;
m1 to m4 are each independently 0 or 1; and
W
1-W
4 are each independently hydrogen, carboxylic acid,
carboxylic acid anhydride, carboxylic acid chloride, sulfonic acid, or sulfonyl
chloride, with the proviso that W
1-W
4 are not all hydrogen.
2. The composition of claim 1, wherein M is nickel.
3. The composition of claim 1, wherein Q
1-Q
4 are sulfur.
4. The composition of claim 1, wherein each X
1-X
4 is independently
-(CH
2)
n1- wherein n1 is 1 to 24, -(V(CH
2)
p)
n2-
where V is oxygen or sulfur and p is 2 or 3 and n2 is 1 to 12, -N(R
2)(CH
2)
n3-
where n3 is 1 to 24 and R
2 is C
1-C
12 alkyl, -C(O)(CH
2)
n4-
where n4 is 1 to 23, -C(O)N(R
3)(CH
2)
n5- where
n5 is 1 to 23 and R
3 is hydrogen or C
1-C
12 alkyl,
-N(R
4)S(O)
2(CH
2)
n6- where n6 is 1 to
24 and R
4 is hydrogen or C
1-C
12 alkyl, -S(CH
2)
n7-
where n7 is 1 to 24, -S(O)(CH
2)
n8- where n8 is 1 to 24, -S(O)
2(CH
2)
n9-
where n9 is 1 to 24, or -S(O)
2N(R
5)(CH
2)
n10-
where n10 is 1 to 24 and R
5 is hydrogen or C
1-C
12 alkyl.
5. The composition of claim 1, wherein at least one of X
1-X
4
is
##STR22##
wherein n13 is 1 to about 12, and the value of the corresponding m1-m4 is one.
6. The composition of claim 1, wherein each occurrence of W
1-W
4
is independently a carboxylic acid, a carboxylic acid anhydride of the formula
-C(O)OC(O)R wherein R is C
1-C
12 alkyl or C
6-
12
aryl, or a carboxylic acid chloride.
7. The composition of claim 1, wherein each occurrence of W
1-W
4
is carboxylic acid.
8. The composition of claim 1, wherein the metal complex has an extinction coefficient
of at least about 10,000 M
-;1cm
-;1 at a wavelength of about
800 to about 2000 nanometers.
9. The composition of claim 1, wherein the metal complex has an extinction coefficient
of at least about 20,000 M
-;1cm
-;1 at a wavelength of about
900 to about 1350 nanometers.
10. The composition of claim 1, wherein the metal complex has an extinction coefficient
of at least about 20,000 M
-;1cm
-;1 at a wavelength of about
1650 to about 1900 nanometers.
11. The composition of claim 1, wherein the metal complex has a fluorescence
and/or phosphorescence quantum yield of less than or equal to 0.05 for an excitation
wavelength of about 800 to about 2000 nanometers.
12. A composition comprising a metal complex having the formula
##STR23##
wherein
M is nickel, palladium, or platinum;
Q
1-Q
4 are each independently sulfur, selenium, or tellurium;
Ar
1-Ar
4 are each independently C
6-C
12
arylene, wherein Ar
1 and Ar
2 may collectively form a C
12-C
24
arylene, and Ar
3 and Ar
4 may collectively form a C
12-C
24
arylene;
each occurrence of R
1-R
4 is independently C
1-C
12
alkyl, C
1-C
12 alkoxy, C
1-C
12 alkylthio,
halogen, hydroxy, nitro, cyano, di(C
1-C
12)alkylamino, or
sulfonamide;
each occurrence of p1-p4 is independently 0, 1, 2, 3, 4, or 5;
each occurrence of Y
1-Y
4 is independently a divalent linking
group having 1 to about 125 carbons;
each occurrence of q1-q4 is independently 0 or 1;
each occurrence of Z
1-Z
4 is independently carboxylic acid,
carboxylic acid anhydride, carboxylic acid chloride, sulfonic acid, or sulfonyl
chloride; and
each occurrence of r1-r4 is independently 0, 1, 2, or 3, with the proviso that
at least one of r1-r4 is at least 1.
13. The composition of claim 12, wherein M is nickel.
14. The composition of claim 12, wherein Q
1-Q
4 are sulfur.
15. The composition of claim 12, wherein Ar
1-Ar
4 are each
independently phenylene, diphenylene, naphthylene, or julolidinylene; or Ar
1
and Ar
2 collectively form a 2,2′-diphenylene and Ar
3
and Ar
4 collectively form a 2,2′-diphenylene.
16. The composition of claim 12, wherein Ar
1-Ar
4 are each phenylene.
17. The composition of claim 12, wherein at least one of R
1-R
4
is di(C
1-C
12)alkylamino and the value of the corresponding
p1-p4 is at least 1.
18. The composition of claim 12, wherein each occurrence of Y
1-Y
4
is independently -(CH
2)
n1- wherein n1 is 1 to 24, -(OCH
2CH
2)
n2-
where n2 is 1 to 12, -N(R
2)(CH
2)
n3- where n3 is
1 to 24 and R
2 is C
1-C
12 alkyl, -C(O)(CH
2)
n4-
where n4 is 1 to 23, -C(O)N(R
3)(CH
2)
n5- where
n5 is 1 to 23 and R
3 is hydrogen or C
1-C
12 alkyl,
-N(R
4)S(O)
2(CH
2)
n6- where n6 is 1 to
24 and R
4 is hydrogen or C
1-C
12 alkyl, -S(CH
2)
n7-
where n7 is 1 to 24, -S(O)(CH
2)
n8- where n8 is 1 to 24, -S(O)
2(CH
2)
n9-
where n9 is 1 to 24, or -S(O)
2N(R
5)(CH
2)
n10-
where n10 is 1 to 24 and R
5 is hydrogen or C
1-C
12 alkyl.
19. The composition of claim 12, wherein each occurrence of Y
1-Y
4
is independently -(CH
2)
n1- wherein n1 is 1 to 24, or
-N(R
2)(CH
2)
n3- where n3 is 1 to 24 and R
2
is hydrogen or C
1-C
12 alkyl.
20. The composition of claim 12, wherein one to three of Y
1-Y
4
comprises a divalent polypeptide, a divalent polysaccharide, or a divalent polynucleotide.
21. The composition of claim 12, wherein each occurrence of Z
1-Z
4
is independently a carboxylic acid, a carboxylic acid anhydride of the formula
-C(O)OC(O)R wherein R is C
1-C
12 alkyl or C
6-C
12
aryl, or a carboxylic acid chloride.
22. The composition of claim 11, wherein each occurrence of Z
1-Z
4
is carboxylic acid.
23. The composition of claim 11, wherein at least two of r1-r4 are at least 1.
24. A composition comprising a metal complex having the formula
##STR24##
wherein
M is nickel, palladium, or platinum;
each occurrence of R
1-R
4 is independently C
1-C
12
alkyl, C
1-C
12 alkoxy, C
1-C
12 alkylthio,
halogen, hydroxy, nitro, cyano, di(C
1-C
12)alkylamino, or
sulfonamide;
each occurrence of p1-p4 is independently 0, 1, 2, 3, 4, or 5;
each occurrence of Y
1-Y
4 is independently a divalent linking
group having 1 to about 125 carbons;
each occurrence of q1-q4 is independently 0 or 1;
each occurrence of Z
1-Z
4 is independently carboxylic acid,
carboxylic acid anhydride, carboxylic acid chloride, sulfonic acid, or sulfonyl
chloride; and
each occurrence of r1-r4 is independently 0, 1, 2, or 3, with the proviso that
at least one of r1-r4 is at least 1.
25. The composition of claim 24, wherein M is nickel.
26. The composition of claim 24, having the formula
##STR25##
wherein M is nickel, palladium, or platinum; each occurrence of R
6 is
independently C
1-C
12 alkyl; each occurrence of X is independently
-CH
2- or -C(O)-; and each occurrence of n11 is independently 1 to 24.
27. The composition of claim 26, comprising a nickel dithiolene complex having
the formula
##STR26##
28. A composition comprising a metal dithiolene complex having the formula
##STR27##
wherein M is nickel, palladium, or platinum; each occurrence of R
6 is
independently C
1-C
12 alkyl; each occurrence of X is independently
-CH
2- or -C(O)-; each occurrence of n11 is independently 1 to 24; and
n12 is 0 to 8.
29. The composition of claim 1 comprising a nickel dithiolene complex having
the formula
##STR28##
##STR29##
wherein M is nickel, palladium, or platinum; Q
1-Q
4 are
each independently sulfur, selenium, or tellurium; W
2 and W
3 are
each independently hydrogen, carboxylic acid, carboxylic acid anhydride, carboxylic
acid chloride, sulfonic acid, or sulfonyl chloride; and each n13 is independently
1 to 12. or a combination thereof.
Description
BACKGROUND
Transition metal dithiolene complexes and their selenium and tellurium
analogs have been extensively studied. Reviews of work in this area include, for
example, U. T. Mueller-Westerhoff and B. Vance, "Dithiolenes and Related Species",
Chapter 16.5 in G. Wilkinson, Ed. "Comprehensive Coordination Chemistry", Pergamon
Press, 1987. Some of these complexes are of interest for their oxidation-reduction
properties, as well as their ability to efficiently absorb near infrared radiation
and thermally dissipate the absorbed energy.
In order to covalently bind a metal dithiolene complex to another molecule, it
would be desirable to begin with a metal dithiolene complexes having a reactive
functional group. In practice, however, it has been difficult to prepare such complexes
because the formation and/or presence of the functional groups has interfered with
metal complexation by the dithiolene ligand. There therefore remains a need for
functionalized metal dithiolene complexes.
BRIEF SUMMARY
Described herein is a composition comprising a metal complex having the
formula (I)
##STR2##
wherein M is nickel, palladium, or platinum; Q
1-Q
4 are
each independently sulfur, selenium, or tellurium; X
1-X
4 are
each independently a divalent linking group having 1 to about 125 carbons; m1 to
m4 are each independently 0 or 1; and W
1-W
4 are each independently
hydrogen, carboxylic acid, carboxylic acid anhydride, carboxylic acid chloride,
sulfonic acid, or sulfonyl chloride, with the proviso that W
1-W
4
are not all hydrogen.
Other embodiments, including functionalized ferrocenyl-substituted metal complexes
and functionalized bis-metal complexes, are described below.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
One embodiment is a composition comprising a functionalized metal complex having
formula (I)
##STR3##
wherein M is nickel, palladium, or platinum; Q
1-Q
4 are
each independently sulfur, selenium, or tellurium; X
1-X
4 are
each independently a divalent linking group having 1 to about 125 carbons; m1 to
m4 are each independently 0 or 1; and W
1-W
4 are each independently
hydrogen, carboxylic acid, carboxylic acid anhydride, carboxylic acid chloride,
sulfonic acid, or sulfonyl chloride, with the proviso that W
1-W
4
are not all hydrogen.
In a preferred embodiment, M is nickel. In another preferred embodiment, Q
1-Q
4
are sulfur.
Although the metal complexes are herein represented for brevity as having
the dithiolene structural unit as follows:
##STR4##
it will be understood that various oxidation states are available to the metal
such that the complex can be represented as any one or more of the redox-related
complexes as shown below
##STR5##
and corresponding to metal oxidation states of 0 to +4. Such structures, and
any others that may be present, are within the scope of the dithiolene structure.
In one embodiment, each occurrence of X
1-X
4 is independently
-(CH
2)
n1- wherein n1 is 1 to 24, -(V(CH
2)
p)
n2-
where V is oxygen or sulfur and p is 2 or 3 and n2 is 1 to 12, -N(R
2)-(CH
2)
n3-
where n3 is 1 to 24 and R
2 is C
1-C
12 alkyl, -C(O)(CH
2)
n4-
where n4 is 1 to 23, -C(O)N(R
3)(CH
2)
n5- where
n5 is 1 to 23 and R
3 is hydrogen or C
1-C
12 alkyl,
-N(R
4)-S(O)
2(CH
2)
n6- where n6 is 1
to 24 and R
4 is hydrogen or C
1-C
12 alkyl, -S(CH
2)
n7-
where n7 is 1 to 24, -S(O)(CH
2)
n8- where n8 is 1 to 24,
-S(O)
2-(CH
2)
n9- where n9 is 1 to 24, or -S(O)
2-N(R
5)-(CH
2)
n10-
wherein n10 is 1 to 24 and R
5 is hydrogen or C
1-C
12
alkyl. It will be understood that either terminus of a given X
1-X
4
group above may be attached to the corresponding W
1-W
4 group,
with the other terminus attached to the corresponding dithiolene carbon. For example,
when X
1 is -N(R
2)(CH
2)
n3-, it may be
attached in the configuration W
1-N(R
2)(CH
2)
n3-(dithiolene)-
or in the configuration W
1-(CH
2)
n3N(R
2)-(dithiolene)-.
In a preferred embodiment each occurrence of W
1-W
4 is independently
carboxylic acid (-C(O)OH); carboxylic acid anhydride (-C(O)OC(O)R) wherein R is
C
1-C
12 alkyl or C
6-C
12 aryl; or carboxylic
acid chloride (-C(O)Cl). In a highly preferred embodiment, each occurrence of W
1-W
4
is independently carboxylic acid.
In another embodiment, at least one of X
1-X
4 comprises a
ferrocenyl complex. For example, at least one of X
1-X
4 may
have the structure of formula (II)
##STR6##
wherein n13 is 1 to about 12, and the value of the corresponding m1-m4 is
one. In other words, X
1 has the divalent ferrocenyl structure shown
above and ml is one, and/or X
2 has the divalent ferrocenyl structure
shown above and m2 is one, and/or X
3 has the divalent ferrocenyl structure
shown above and m3 is one, and/or X
4 has the divalent ferrocenyl structure
shown above and m4 is one. In a preferred embodiment, at least two of X
1-X
4
have the divalent ferrocenyl structure shown above and the values of the
corresponding at least two of m1-m4 are one. It will be understood that as used
herein, the cyclopentadienyl rings of all ferrocenyl moieties shown and described
in this application may include alkyl-substituted analogs, preferably branched
or unbranched C
1-C
8 alkyl-sustituted analogs, including,
for example, methycyclopentadienyl, dimethylcyclopentadienyl, trimethylcyclopentadieny,
tetramethylcyclopentadienyl, and pentamethylcyclopentadienyl. Varying the degree
of alkylation of cyclopentadienyl rings may be used to control the maximum absorption
wavelength of the complex.
In another embodiment, the metal complex has one of the structures of Formula
(IIIa)-(IIIc):
##STR7##
wherein M, Q
1-Q
4, W
2 and W
3 are
as defined above for formula (I), and n13 is as defined above for Formula (II).
Compounds of Formula (III) have the advantage of absorbing strongly in the region
of about 1600 to about 1900 nanometers.
Preferably, each occurrence of W
1-W
4 is independently
carboxylic acid (-C(O)OH); carboxylic acid anhydride (-C(O)OC(O)R) wherein R is
C
1-C
12 alkyl or C
6-C
12 aryl; or carboxylic
acid chloride (-C(O)Cl). In a highly preferred embodiment, each occurrence of W
1-W
4
is independently carboxylic acid. According, in a preferred embodiment, the
functionalized metal complex has formula (IV)
##STR8##
Another embodiment is a composition comprising a functionalized metal complex
having formula (V)
##STR9##
wherein M is nickel, palladium, or platinum; Q
1-Q
4 are
each independently sulfur, selenium, or tellurium; Ar
1-Ar
4 are
each independently C
6-C
12 arylene, wherein Ar
1 and
Ar
2 may collectively form a C
2-C
24 arylene, and
Ar
3 and Ar
4 may collectively form a C
12-C
24
arylene; each occurrence of R
1-R
4 is independently
C
1-C
12 alkyl, C
1-C
12 alkoxy, C
1-C
12
alkylthio, halogen, hydroxy, nitro, cyano, di(C
1-C
12)alkylamino,
or sulfonamide; each occurrence of p1-p4 is independently 0, 1, 2, 3, 4, or 5;
each occurrence of Y
1-Y
4 is independently a divalent linking
group having 1 to about 125 carbons; each occurrence of q1-q4 is independently
0 or 1; each occurrence of Z
1-Z
4 is independently carboxylic
acid, carboxylic acid anhydride, carboxylic acid chloride, sulfonic acid, or sulfonyl
chloride; and each occurrence of r1-r4 is independently 0, 1, 2, or 3, with the
proviso that at least one of r1-r4 is at least 1.
Referring to formula (V), in a preferred embodiment, M is nickel. In another
preferred embodiment, Q
1-Q
4 are sulfur. In addtion, Ar
1-Ar
4
are each independently phenylene, diphenylene, naphthylene, or julolidinylene;
or Ar
1 and Ar
2 collectively form a 2,2′-diphenylene
and Ar
3 and Ar
4 collectively form a 2,2′-diphenylene,
wherein 2,2′-diphenylene is understood to have the structure
##STR10##
In a preferred embodiment, Ar
1-Ar
4 are each phenylene.
Referring still to formula (V), in one embodiment at least one of R
1-R
4
is an electron donating substituent such as di(C
1-C
12)alkylamino,
and the value of the corresponding at least one p1-p4 is at least 1. It may be
preferred that at least two of R
1-R
4 are electron donating
substituents such as di(C
1-C
12)alkylamino, and the values
of the corresponding at least two of p1 -p4 are at least 1.
In one embodiment, each occurrence of Y
1-Y
4 is independently
-(CH
2)
n1- wherein n1 is 1 to 24, -(OCH
2CH
2)
n2-
where n2 is 1 to 12, -N(R
2)(CH
2)
n3- where n3 is
1 to 24 and R
2 is C
1-C
12 alkyl, -C(O)(CH
2)
n4-
where n4 is 1 to 23, -C(O)-N(R
3)-(CH
2)
n5- where
n5 is 1 to 23 and R
3 is hydrogen or C
1-C
12 alkyl,
-N(R
4)S(O)
2(CH
2)
n6- where n6 is 1 to
24 and R
4 is hydrogen or C
1-C
12 alkyl, -S(CH
2)
n7-
where n7 is 1 to 24, -S(O)(CH
2)
n8- where n8 is 1 to 24, -S(O)
2(CH
2)
n9-
where n9 is 1 to 24, or -S(O)
2-N(R
5)(CH
2)
n10-
where n10 is 1 to 24 and R
5 is hydrogen or C
1-C
12 alkyl.
It will be understood that either terminus of a given Y
1-Y
4 group
above may be attached to the corresponding Z
1-Z
4 group, with
the other terminus attached to the corresponding Ar
1-Ar
4.
For example, when Y
1 is -N(R
2)(CH
2)
n3-,
it may be attached in the configuration Z
1-N(R
2)(CH
2)
n3-Ar
1-
or in the configuration Z
1-(CH
2)
n3N(R
2)-Ar
1-.
In a preferred embodiment, each occurrence of Y
1-Y
4 is
independently
-(CH
2)
n1- wherein n1 is 1 to 24, or -N(R
2)(CH
2)
n3-
where n3 is 1 to 24 and R
2 is hydrogen or C
1-C
12 alkyl.
In another embodiment, at least one of Y
1-Y
4 comprises a
divalent polypeptide, a divalent polysaccharide, or a divalent polynucleotide.
Still referring to formula (V), in a preferred embodiment each occurrence of
Z
1-Z
4 is independently carboxylic acid (-C(O)OH); carboxylic
acid anhydride (-C(O)OC(O)R) wherein R is C
1-C
12 alkyl or
C
6-C
12 aryl; or carboxylic acid chloride (-C(O)Cl). In a
highly preferred embodiment, each occurrence of W
1-W
4 is
independently carboxylic acid.
In another preferred embodiment, at least two of r1-r4 are at least 1.
Another embodiment is a composition comprising a functionalized metal dithiolene
complex having formula (VI)
##STR11##
wherein M is nickel, palladium, or platinum; each occurrence of R
1-R
4
is independently C
1-C
12 alkyl, C
1-C
12
alkoxy, C
1-C
12 alkylthio, halogen, hydroxy, nitro,
cyano, di(C
1-C
12)alkylamino, or sulfonamide; each occurrence
of p1-p4 is independently 0, 1, 2, 3, 4, or 5; each occurrence of Y
1-Y
4
is independently a divalent linking group having 1 to about 125 carbons;
each occurrence of q1-q4 is independently 0 or 1; each occurrence of Z
1-Z
4
is independently carboxylic acid, carboxylic acid anhydride, carboxylic acid
chloride, sulfonic acid, or sulfonyl chloride; and each occurrence of r1-r4 is
independently 0, 1, 2, or 3, with the proviso that at least one of r1-r4 is at
least 1.
In a preferred embodiment, M is nickel.
Another embodiment is a composition comprising a functionalized metal dithiolene
complex having formula (VII)
##STR12##
wherein M is nickel, palladium, or platinum; each occurrence of R
6 is
independently C
1-C
12 alkyl; each occurrence of X is independently
-CH
2- or -C(O); and each occurrence of n11 is independently 1 to 24.
Another embodiment is a composition comprising a functionalized bis-metal
dithiolene complex having formula (VIII)
##STR13##
wherein n12 is 0 to about 8, preferably 1 to about 6; and M, R
6,
X, and n11 are as defined above for formula (VI).
Another embodiment is a composition comprising a functionalized nickel dithiolene
complex having formula (IX)
##STR14##
Compounds of the generalized formula (VII) can be obtained by first synthesizing
the two halves of each ligand, or protected derivatives thereof, in the form of
their aldehydes (A) (e.g., A1 and A2, below); then condensing the two halves by
one of several methods, such as benzoin condensation or Corey-Seeback umpolung
reaction or the like to form B (e.g., B1, below) or one of its derivatives; then
converting B to the dithiolene complex VI as described in the literature.
##STR15##
Compounds of the generalized formula (VIII), in which the extinction coefficients
are multiplied by attaching several dithiolenes to the same backbone, can be prepared
using the syntheses shown below in which (VII) is an intermediate. By reaction
with SOCl
2 or (COCl)
2, (VII) is converted to the acid chloride,
which then is added to the polyamine C dissolved in ether or dichloromethane. After
addition of an aqueous sodium acetate solution to hydrolyze the unreacted acid
chloride functions and acidification to pH 5, the bound dithiolene is isolated
and purified.
##STR16##
Compounds of structure (IX) may be synthesized by the route shown below.
Starting from the commercially available cyano-aldehyde D (Aldrich), a benzoin
condensation with benzaldehyde produces the benzoin intermediate E. Refluxing E
with phosphorus pentasulfide in dioxane, followed by addition of metal chloride
(NiCl
2 in the case of (IX), M=Ni) in water and another period of reflux
produces the dithiolene F and several byproducts. Separation of F by column chromatography
is followed by hydrolysis of the cyano groups through stirring F at room temperature
for 24 h in a solution of concentrated HCl in glacial acetic acid to produce (IX).
##STR17##
The functionalized metal complex preferably has an extinction coefficient of
at least about 10,000 M
-;1cm
-;1 at a wavelength of about
800 to about 2000 nanometers. The extinction coefficient may preferably be at least
about 20,000 M
-;1cm
-;1, more preferably at least about 30,000
M
-;1cm
-;1, still more preferably at least about 40,000 M
-;1cm
-;1,
yet more preferably at least about 60,000 M
-;1cm
-;1, even
more preferably at least about 80,000 M
-;1cm
-;1. In one embodiment,
the wavelength may preferably be at least about 900 nm and up to about 1350 nm.
In another embodiment, the wavelength may preferably be at least about 1650 nm
and up to about 1900 nm.
The functionalized metal complex preferably does not significantly fluoresce
or phosphoresce. For example, the functionalized metal complex may have a fluorescence
and/or phosphorescence quantum yield of less than or equal to 0.05 for an excitation
wavelength of about 800 to about 2000 nanometers. When the metal complex has such
low quantum yield for fluorescence and phosphorescence, essentially all absorbed
near infrared (NIR) light energy is converted to thermal energy that can be used
to heat up the immediate environment of the complex.
The functionalized metal complexes described herein are useful as redox catalysts,
as efficient converters of near-infrared radiation to thermal energy, and as conductors
of electric current. They may also exhibit unusual magnetic properties. They are
also useful as substrates in passive Q-switch and mode-locking applications for
different IR lasers (see, for example, U.S. Pat. No. 3,743,964 to Drexhage et al.).
They are further useful as redox potential driven electron carriers and cation
carriers through artificial membranes (see, for example, J. J. Grimaldi and J.
M. Lehn,
J. Am. Chem. Soc., 1979, volume 101, pages 1333 ff.; and A. Ohki,
M. Takagi, and K. Ueno,
Chem. Lett., 1980, pages 1591 ff.).
The invention is further illustrated by the following non-limiting examples.
EXAMPLE 1
This example describes preparation of a functionalized, bis(ferrocenyl)-substituted
nickel dithiolene complex. The procedure of Wilkes et al. was used to react α-chloroacetylferrocene
(obtained from Aldrich) with ferrocene and aluminum chloride in dichloromethane
to produce chloroacetylferrocene. This was reacted with potassium ethylxanthate
in ethanol; the product of this reaction was cyclized to form a ferrocenyl dithiocarbonate
(4-ferrocenyl-1,3-dithiole-2-one). (See A. E. Underhill, A. Charlton, S. B. Wilkes,
I. R. Butler, A. Kobayashi, and H. Kobayashi,
Synth. Met., 1995, volume
70, pages 1101 ff.)
##STR18##
The ferrocenyl dithiocarbonate was reacted with one equivalent of succinic anhydride
and three equivalents of aluminum chloride. An 82.7% yield of 4-(1′-succinylferrocenyl)-1,3-dithiole-2-one
was obtained following purification by column chromatography.
##STR19##
The 6,7-(1′-succinyl)ferrocenyl-3,4-dithiole-2-one was reacted with potassium
hydroxide in methanol to form the dithiolate dianion; addition of nickel chloride
hexahydrate in methanol/HCl yielded the succinyl-substituted diferrocenyl nickel
complex, bis([1′-succinyl ferrocenyl]ethylene-1,2-dithiolato) nickel (II).
The product was converted to the neutral nickel (IV) complex by oxidizing with
air.
##STR20##
Following oxidation, workup, and isolation of the product mixture, the
complex was dissolved in an aqueous 10% KOH solution and filtered. Product was
precipitated by acidifying the solution to pH 3, filtered, and washed with water
and then hexane to afford the purified complex in 48% yield based on the dithiolene
ligand. mp >260° C.; APcI
-; MS m/e 805.7 (M
-;,
calc. 805.88); Near IR λ
1max/λ
2max (CH
2Cl
2)
1106 nm (broad, strong)/735 nm, (DMF) 1140 nm (broad, strong)/752 nm, (DMF) 1007
nm (monoanionic species, (H
2O, pH 3) 1180 nm (broad, strong)/748 nm,
(H
2O, pH 7.5) 1068 nm, (H
2O, pH 9) 163 nm.
EXAMPLE 2
This example summarized procedures used in multiple preparations of a functionalized
bis(dialkylamino)-substituted nickel dithiolene complex. The commercially available
(Aldrich) material 4-(2-cyanoethyl-methylamino)benzaldehyde was subjected to a
benzoin condensation with benzaldehyde (NaCN catalyst in either ethanol/water or
N,N-dimethylformamide/water at temperatures varying between 20° C. and the
boiling point of the reaction mixture) to produce a mixture of products, of which
the desired benzoin was a more or less abundant part. Optimization of the reaction
conditions allowed the synthesis of the benzoin as the major product. The purification
involved repeated column chromatography and recrystallizations for an overall yield
of pure benzoin varying between 25 and 60%. In this manner, sufficient quantities
of the benzoin were obtained to proceed to the next step.
The benzoin was treated with P
4S
10 in dioxane (reflux,
2 h) and the mixture was reacted at reflux with NiCl
2-6H
2O
in water containing HCl to produce the dithiolene complex carrying two cyano functionalities.
This complex was purified by column chromatography.
In the final step, the dicyano derivative was hydrolyzed (anyhydrous HCl/acetic
acid, room temperature, 2 days) to produce the desired diacid.
The product was recrystallized from ethyl acetate and characterized by Vis-NIR
spectroscopy (λ
max=1058 nm) and APcI mass spectrometry. The success
of this synthetic approach was not necessarily expected because the cyano group
could have interfered in the sulfurization reaction, and the final hydrolysis could
have destroyed the dithiolene complex.
While the invention has been described with reference to a preferred embodiment,
it will be understood by those skilled in the art that various changes may be made
and equivalents may be substituted for elements thereof without departing from
the scope of the invention. In addition, many modifications may be made to adapt
a particular situation or material to the teachings of the invention without departing
from essential scope thereof Therefore, it is intended that the invention not be
limited to the particular embodiment disclosed as the best mode contemplated for
carrying out this invention, but that the invention will include all embodiments
falling within the scope of the appended claims.
All cited patents, patent applications, and other references are incorporated
herein by reference in their entirety.
*
