PHOTOCHROMIC Pt(II)-M(I) HETEROTRINUCLEAR COMPLEXES, PREPARATION METHOD THEREFOR AND USE THEREOF

Abstract

Pt.sub.2M heterotrinuclear metal-organic alkynyl complexes have a structure of formula (I): [Pt.sub.2M(-PR.sub.2CH.sub.2PRCH.sub.2PR.sub.2).sub.2(CCR).sub.2(CCR).sub.2].sup.+.sub.mA.sup.m. In formula (I), represents a bridging ligand; PR.sub.2CH.sub.2PRCH.sub.2PR.sub.2 is a type of tridentate phosphine ligands; the subscript number of each letter represents the number of each group. The complexes present phosphorescent emission, and the color distribution of the emitted light is relatively broad from blue-green to orange-red. The complexes can be used as photoluminescent materials in the fields of displays, lighting, sensors and biomarkers. Among the complexes, Cu complexes also exhibit reversible self-recovery photochromic performance. Under UV irradiation, the complexes change from a colorless or light color state to a dark color state rapidly, and after stopping UV irradiation, they gradually return to the light color state.

Claims

1. A Pt.sub.2M heterotrinuclear metal-organic alkynyl complex, and the structure is shown in the following formula (I):
[Pt.sub.2M(-PR.sub.2CH.sub.2PRCH.sub.2PR.sub.2).sub.2(CCR).sub.2(CCR).sub.2].sup.+.sub.mA.sup.m;(I) wherein, represents bridging; PR.sub.2CH.sub.2PRCH.sub.2PR.sub.2 is a type of tridentate phosphine ligand; the subscript number of each letter indicates the number of each group; M is Au(I), Ag(I) or Cu(I); R, R and R are identical or different, independently selected from groups of alkyl, alkenyl, alkynyl, aryl, or heteroaryl that are unsubstituted or optionally substituted by one, two or more R.sup.1; R.sup.1 is selected from groups of alkyl, alkenyl, alkynyl, aryl, halogen (F, Cl, Br, I), trihalomethyl (CX.sub.3, XF, Cl, Br), NO.sub.2, CN, OR.sup.3, N(R.sup.4).sub.2, COR.sup.5, SO.sub.3H, S(O).sub.2R.sup.6, S(O)R.sup.6, P(O)(R.sup.7).sub.2, tertiary amine cation (N(R.sup.8).sub.3.sup.+), or N-substituted pyridyl cation [C.sub.5H.sub.4N(R.sup.9).sup.+], which are unsubstituted or optionally substituted by one, two or more R.sup.2; R.sup.2 is selected from groups of alkyl, alkenyl, alkynyl, aryl, halogen (F, Cl, Br, I), trihalomethyl (CX.sub.3, XF, Cl, Br), NO.sub.2, CN, OR.sup.3, N(R.sup.4).sub.2, COR.sup.5, SO.sub.3H, S(O).sub.2R.sup.6, S(O)R.sup.6, P(O)(R.sup.7).sub.2, tertiary amine cation (N(R.sup.8).sub.3.sup.+), or N-substituted pyridyl cation [C.sub.5H.sub.4N(R.sup.9).sup.+]; R.sup.3 is alkyl, aryl, or heteroaryl; R.sup.4 is identical or different, independently selected from H, alkyl, aryl, or heteroaryl; R.sup.5 is H, OH, alkyl, aryl, or heteroaryl; R.sup.6, R.sup.7, R.sup.8 and R.sup.9 are alkyl, aryl, or heteroaryl; A.sup.m is a monovalent or bivalent anion, and m is 1 or 2, and said anion is, for example, ClO.sub.4.sup., PF.sub.6.sup., SbF.sub.6.sup., BF.sub.4.sup., B(C.sub.6H.sub.5).sub.4.sup., CF.sub.3SO.sub.3.sup. or SiF.sub.6.sup.2.

2. The complex according to claim 1, characterized in that, the stereostructure of said complex of formula (I) is represented as follows: ##STR00003##

3. The complex according to claim 1, characterized in that, in formula (I), said A.sup.m is selected from ClO.sub.4.sup., PF.sub.6.sup., SbF.sub.6.sup., BF.sub.4.sup., B(C.sub.6H.sub.5).sub.4.sup., CF.sub.3SO.sub.3.sup. or SiF.sub.6.sup.2, and m is 1 or 2; R is selected from groups of C.sub.1-6 alkyl, C.sub.1-6 alkenyl, C.sub.1-6 alkynyl, C.sub.6-12 aryl or 6- to 20-membered heteroaryl that are unsubstituted or optionally substituted by 1-5 substituents of C.sub.1-6 alkyl, aryl, halogen (F, Cl, Br, I), trihalomethyl (CX.sub.3, XF, Cl, Br), NO.sub.2, CN, OR.sup.3, N(R.sup.4).sub.2, COR.sup.5, SO.sub.3H, S(O).sub.2R.sup.6, S(O)R.sup.6, P(O)(R.sup.7).sub.2, tertiary amine cation (N(R.sup.8).sub.3.sup.+), or N-substituted pyridyl cation [C.sub.5H.sub.4N(R.sup.9).sup.+]; R and R are identical or different, independently selected from groups of C.sub.1-6 alkyl, C.sub.1-6 alkenyl, C.sub.1-6 alkynyl, C.sub.6-12 aryl or 6- to 20-membered heteroaryl that are unsubstituted or optionally substituted by 1-5 substituents of C.sub.1-6 alkyl, C.sub.1-6 alkenyl, C.sub.1-6 alkynyl, aryl, halogen, trihalomethyl(-CX.sub.3, XF, Cl, Br), NO.sub.2, CN, OR.sup.3, N(R.sup.4).sub.2, COR.sup.5, SO.sub.3H, S(O).sub.2R.sup.6, S(O)R.sup.6, P(O)(R.sup.7).sub.2, tertiary amine cation (N(R.sup.8).sub.3.sup.+), or N-substituted pyridyl cation [C.sub.5H.sub.4N(R.sup.9).sup.+]; wherein R.sup.3 is alkyl, aryl, or heteroaryl; R.sup.4 is identical or different, independently selected from H, alkyl, aryl, or heteroaryl; R.sup.5 is H, OH, alkyl, aryl, or heteroaryl; R.sup.6, R.sup.7, R.sup.8 and R.sup.9 are alkyl, aryl, or heteroaryl.

4. The complex according to claim 1, characterized in that, said Pt.sub.2M heterotrinuclear metal-organic alkynyl complex is selected from the following structures: ##STR00004##

5. A preparation method of the complex according to claim 1, characterized by, comprising the following steps: 1) dpmp and M-solvent complex reacting in a solvent to obtain an intermediate; 2) said intermediate obtained in step 1) reacting with Pt(PPh.sub.3).sub.2(CCR)(CCR) in a solvent to obtain said complex of formula (I); wherein, said dpmp stands for bis((diphenylphosphino)methyl) (phenyl)phosphine, said PPh.sub.3 stands for triphenylphosphine.

6. The preparation method according to claim 5, characterized in that, said M-solvent complex is selected from [Au(tht).sub.2].sub.m(A.sup.m) or [Ag(tht)].sub.m(A.sup.m) or [Cu(MeCN).sub.4].sub.m(A.sup.m), wherein tht is tetrahydrothiophene, MeCN is acetonitrile.

7. The preparation method according to claim 5, characterized in that, in said preparation method of said complex of formula (I), said solvent is halogenated hydrocarbon.

8. The preparation method according to claim 5, characterized in that, the molar ratio of dpmp:Au(I), Ag(I) or Cu(I) ion:Pt(PPh.sub.3).sub.2(CCR)(CCR) is 2-3.0:1-1.5:2-3.0.

9. Use of the complex of formula (I) according to claim 1 as a photochromic material in the fields of displays, lighting, sensors, and biomarkers.

10. Use of the complex of formula (I) according to claim 1 in the fields of trademark anti-counterfeiting, information encryption and decryption, and product identification based on their reversible self-recovery photochromic performance.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0047] FIG. 1: In Example 12, the absorption spectra of complex 5 before and after UV irradiation at 365 nm.

[0048] FIG. 2: In Example 12, the absorption spectral changes of complex 5 after stopping UV irradiation at 365 nm.

[0049] FIG. 3: In Example 7, the relationship between the absorbance values of complex 5 at 550 nm and the irradiation times before and after the UV irradiation at a wavelength of 365 nm (fatigue test).

[0050] FIG. 4: In Example 12, the .sup.1HNMR spectra of complex 5 in 10 hours before and after ultraviolet irradiation at a wavelength of 365 nm.

EXAMPLES

[0051] To make the objects, technical solutions and technical effects clearer, the present invention will be further illustrated in detail below in combination with the drawings and the examples. It should be understood that the examples described in the description are only to explain the invention and are not intended to limit the invention.

[0052] In the following examples, dpmp stands for bis((diphenylphosphino)methyl)(phenyl)phosphine, Ph stands for phenyl, tht stands for tetrahydrothiophene, PPh.sub.3 stands for triphenylphosphine, MeCN is acetonitrile, and ClO.sub.4.sup. is perchlorate.

Example 1: Preparation of Pt.SUB.2.Au Complex [Pt.SUB.2.Au(-Dpmp).SUB.2.(CCC.SUB.6.H.SUB.5.).SUB.4.](ClO.SUB.4.) (Complex 1)

[0053] To a dichloromethane solution (20 mL) of dpmp (50.6 mg, 0.1 mmol) was added [Au(tht).sub.2](ClO.sub.4) (23.6 mg, 0.05 mmol) with stirring until the solid was completely dissolved. Upon stirring for 5 mins, platinum complex Pt(PPh.sub.3).sub.2(CCPh).sub.2 (92.2 mg, 0.1 mmol) was added to the above solution. The color of the solution changed from colorless or light color to light yellow after the platinum complex was dissolved rapidly. The solution was stirred for 4 hours at room temperature, then concentrated to 2 mL. The product was then purified by silica gel column chromatography using dichloromethane-acetone (10:1) as eluent.

[0054] Yield: 83%. Elemental analysis C.sub.96H.sub.78AuClO.sub.4P.sub.6Pt.sub.2, calculated: C, 54.80; H, 3.74. Found: C, 54.73; H, 3.78. ESI-MS (%): 2004.9 (100) [M-ClO.sub.4].sup.+. .sup.1H-NMIR (CD.sub.2Cl.sub.2, ppm): 7.86-7.80 (m, 12H), 7.72-7.67 (m, 8H), 7.40-7.33 (m, 12H), 7.17-7.11 (m, 6H), 7.05-6.81 (m, 24H), 6.47-6.46 (d, 4H, J=7.4 Hz), 6.28-6.26 (d, 4H, J=7.0 Hz), 4.40-4.23 (m, 8H). .sup.31P-NMR (CD.sub.2Cl.sub.2, ppm): 17.7 (m, 2P, J.sub.PP=32.3 Hz), 4.4 (t, 4P, J.sub.PP=28.3 Hz, J.sub.PtP=2676 Hz). IR (KBr, cm.sup.1): 2103 (m), 1102 (s).

Example 2: Preparation of Pt.SUB.2.Ag Complex [Pt.SUB.2.Ag(-Dpmp).SUB.2.(CCC.SUB.6.H.SUB.5.).SUB.4.](ClO.SUB.4.) (Complex 2)

[0055] The preparation method was similar to that in Example 1, except that Au(tht)(ClO.sub.4) was replaced by [Ag(tht).sub.2](ClO.sub.4).

[0056] Yield: 79%. Elemental analysis C.sub.96H.sub.78AgClO.sub.4P.sub.6Pt.sub.2, calculated: C, 57.22; H, 3.90. Found: C, 57.19; H, 3.96. ESI-MS (%): 1915.6 (100) [M-ClO.sub.4].sup.+. .sup.1H-NMR (CD.sub.2Cl.sub.2, ppm): 7.80-7.73 (m, 12H), 7.60-7.55 (m, 8H), 7.40-7.30 (m, 12H), 7.21-7.16 (m, 6H), 7.06-7.00 (m, 12H), 6.93-6.84 (m, 12H), 6.58-6.56 (d, 4H, J=7.2 Hz), 6.27-6.25 (d, 4H, J=7.1 Hz), 3.97-3.90 (m, 4H), 3.74-3.69 (m, 4H). .sup.31P-NMR (CD.sub.2Cl.sub.2, ppm): 10.9 (t, 4P, J.sub.PP=37.4 Hz, J.sub.PtP=2622 Hz), 13.0 (m, 2P, J.sub.PP=43.0 HZ, J.sub.AgP=496 Hz). IR (KBr, cm.sup.1): 2104 (w), 1103 (s).

Example 3: Preparation of Pt.SUB.2.Cu Complex [Pt.SUB.2.Cu(-Dpmp).SUB.2.(CCC.SUB.6.H.SUB.5.).SUB.4.](ClO.SUB.4.) (Complex 3)

[0057] The preparation method was similar to that in Example 1, except that Au(tht)(ClO.sub.4) was replaced by [Cu(MeCN).sub.4](ClO.sub.4).

[0058] Yield: 75%. Elemental analysis C.sub.96H.sub.78ClCuO.sub.4P.sub.6Pt.sub.2.H.sub.2O, calculated: C, 57.98; H, 4.05. Found: C, 58.04; H, 4.12. FIRMS m/z (%):1870.3123 (100) [M-ClO.sub.4].sup.+, calculated: 1870.3124. .sup.1H-NMR (CD.sub.2Cl.sub.2, ppm): 8.02-7.98 (m, 4H), 7.89-7.84 (m, 8H), 7.52-7.49 (t, 4H, J=7.3 Hz), 7.44-7.35 (m, 10H), 7.26-7.17 (m, 12H), 7.13-7.10 (t, 4H, J=7.5 Hz), 7.03-7.00 (t, 8H, J=7.6 Hz), 6.93-6.81 (m, 8H), 6.69-6.65 (t, 4H, J=7.8 Hz), 6.53-6.51 (d, 4H, J=7.2 Hz), 6.04-6.02 (d, 4H, J=7.9 Hz), 3.95-3.80 (m, 4H), 3.71-3.63 (m, 4H). .sup.31P-NMR (CD.sub.2Cl.sub.2, ppm): 11.2 (t, 4P, J.sub.PP=37.2 Hz, J.sub.PtP=2548 Hz), 13.4 (m, 2P, J.sub.PP=41.0 Hz). IR (KBr, cm.sup.1): 2115 (w), 1101 (s).

Example 4: Preparation of Pt.SUB.2.Cu Complex [Pt.SUB.2.Cu(-Dpmp).SUB.2.(CCC.SUB.6.H.SUB.4.Bu.SUP.t.-4).SUB.4.](ClO.SUB.4.) (Complex 4)

[0059] The preparation method was similar to that in Example 1, except that Pt(PPh.sub.3).sub.2(CCC.sub.6H.sub.5).sub.2 was replaced by Pt(PPh.sub.3).sub.2(CCC.sub.6H.sub.4Bu.sup.t-4).sub.2, and [Au(tht).sub.2](ClO.sub.4) was replaced by [Cu(MeCN).sub.4](ClO.sub.4).

[0060] Yield: 79%. Elemental analysis C.sub.112H.sub.110ClCuO.sub.4P.sub.6Pt.sub.2, calculated: C, 61.28; H, 5.05. Found: C, 61.40; H, 5.12. HRMS m/z (%): 2095.5614 (100) [M-ClO.sub.4].sup.+, calculated: 2095.5644. .sup.1H-NMR (CD.sub.2Cl.sub.2, ppm): 7.98-7.93 (m, 4H), 7.87-7.84 (m, 8H), 7.54-7.50 (t, 4H, J=7.3 Hz), 7.43-7.36 (m, 10H), 7.25-7.19 (m, 12H), 7.14-7.10 (t, 4H, J=7.3 Hz), 7.04-7.00 (t, 8H, J=7.4 Hz), 6.87-6.85 (d, 4H, J=8.0 Hz), 6.69-6.67 (d, 4H, J=7.7 Hz), 6.54-6.52 (d, 4H, J=7.5 Hz), 5.98-5.96 (d, 4H, J=7.0 Hz), 3.82-3.65 (m, 8H), 1.16 (s, 18H), 1.13 (s, 18H). .sup.31P-NMR (CD.sub.2Cl.sub.2, ppm): 10.7 (m, 4P, J.sub.PP=37.2 Hz, J.sub.PtP=2592 Hz), 14.5 (m, 2P, J.sub.PP=40.2 Hz). IR (KBr, cm.sup.1): 2112 (w), 1101 (s).

Example 5: Preparation of Pt.SUB.2.Cu Complex [Pt.SUB.2.Cu(-Dpmp).SUB.2.(CCC.SUB.6.H.SUB.4.CF.SUB.3.-4).SUB.4.](ClO.SUB.4.) (Complex 5)

[0061] The preparation method was similar to that in Example 1, except that Pt(PPh.sub.3).sub.2(CCC.sub.6H.sub.5).sub.2 was replaced by Pt(PPh.sub.3).sub.2(CCC.sub.6H.sub.4CF.sub.3-4).sub.2, and [Au(tht).sub.2](ClO.sub.4) was replaced by [Cu(MeCN).sub.4](ClO.sub.4).

[0062] Yield: 73%. Elemental analysis C.sub.100H.sub.74ClCuF.sub.12O.sub.4P.sub.6Pt.sub.2, calculated: C, 53.56; H, 3.33. Found: C, 53.27; H, 3.49. FIRMS m/z (%): 2142.2597 (100) [M-ClO.sub.4].sup.+. Calculated: 2142.2623. .sup.1H-NMR (CD.sub.2Cl.sub.2, ppm): 7.99-7.94 (m, 4H), 7.87-7.83 (m, 8H), 7.51-7.47 (t, 4H, J=7.3 Hz), 7.41-7.33 (m, 10H), 7.27-7.17 (m, 12H), 7.11-7.07 (t, 4H, J=7.6 Hz), 7.03-6.99 (t, 8H, J=7.6 Hz), 6.43-6.36 (m, 8H), 6.22-6.20 (d, 4H, J=8.7 Hz), 5.95-5.93 (d, 4H, J=8.7 Hz), 3.91-3.79 (m, 4H), 3.67-3.59 (m, 4H). .sup.31P-NMR (CD.sub.2Cl.sub.2, ppm): 11.1 (m, 4P, J.sub.PP=37.3 Hz, J.sub.PtP=2596 Hz), 14.1 (m, 2P, J.sub.PP=42.2 Hz), IR (KBr, cm.sup.1): 2115 (w), 1102 (s).

Example 6: Preparation of Pt.SUB.2.Cu Complex [Pt.SUB.2.Cu(-Dpmp).SUB.2.(CCC.SUB.6.H.SUB.4.CF.SUB.3.-2,4).SUB.4.](ClO.SUB.4.) (Complex 6)

[0063] The preparation method was similar to that in Example 1, except that Pt(PPh.sub.3).sub.2(CCC.sub.6H.sub.5).sub.2 was replaced by Pt(PPh.sub.3).sub.2(CCC.sub.6H.sub.4CF.sub.3-2,4).sub.2, and [Au(tht).sub.2](ClO.sub.4) was replaced by [Cu(MeCN).sub.4](ClO.sub.4).

[0064] Yield: 67%. Elemental analysis C.sub.104H.sub.70ClCuF.sub.24O.sub.4P.sub.6Pt.sub.2, calculated: C, 49.67; H, 2.81. Found: C, 49.60; H, 2.84. HRMS m/z (%): 2414.2131 (100) [M-ClO.sub.4].sup.+. Calculated: 2414.2119. .sup.1H-NMR (CD.sub.2Cl.sub.2, ppm): 8.02-7.96 (m, 8H), 7.88-7.81 (m, 4H), 7.49 (s, 2H), 7.45-7.36 (m, 10H), 7.28-7.22 (m, 12H), 7.20 (d, 4H, J=7.9 Hz), 7.12 (t, 4H, J=7.7 Hz), 6.98 (t, 4H, J=7.6 Hz), 6.84 (t, 8H, J=8.1 Hz), 6.48 (d, 2H, J=8.3 Hz), 6.29 (d, 2H, J=8.3 Hz), 6.09 (d, 2H, J=8.0 Hz), 4.11-3.97 (m, 4H), 3.80-3.67 (m, 4H). .sup.31P-NMR (CD.sub.2Cl.sub.2, ppm): 11.5 (m, 4P, J.sub.PP=37.1 Hz, J.sub.PtP=2587 Hz), 14.0 (m, 2P, J.sub.PP=42.7 Hz), IR (KBr, cm.sup.1): 2116 (w), 1102 (s).

Example 7: Preparation of Pt.SUB.2.Cu Complex [Pt.SUB.2.Cu(-Dpmp).SUB.2.(CCC.SUB.6.H.SUB.4.CN-4).SUB.4.](ClO.SUB.4.) (Complex 7)

[0065] The preparation method was similar to that in Example 1, except that Pt(PPh.sub.3).sub.2(CCC.sub.6H.sub.5).sub.2 was replaced by Pt(PPh.sub.3).sub.2(CCC.sub.6H.sub.4CN-4).sub.2, and [Au(tht).sub.2](ClO.sub.4) was replaced by [Cu(MeCN).sub.4](ClO.sub.4).

[0066] Yield: 72%. Elemental analysis C.sub.100H.sub.74ClCuN.sub.4O.sub.4P.sub.6Pt.sub.2, calculated: C, 58.00; H, 3.60. Found: C, 57.71; H, 3.78. HRMS m/z (%): 1970.2901 (100) [M-ClO.sub.4].sup.+. Calculated: 1970.2937. .sup.1H-NMR (d-DMSO, ppm): 8.13-8.05 (m, 4H), 7.88-7.81 (m, 8H), 7.59-7.39 (m, 14H), 7.31-7.20 (m, 16H), 7.12-7.02 (m, 16H), 6.28 (d, 4H, J=8.3 Hz), 6.00 (d, 4H, J=8.4 Hz), 4.47-4.26 (m, 4H), 3.91-3.76 (m, 4H). .sup.31P-NMR (d-DMSO, ppm): 11.3 (m, 4P, J.sub.PP=37.1 Hz, J.sub.PtP=2519 Hz), 11.1 (m, 2P, J.sub.PP=39.0 Hz), IR (KBr, cm.sup.1): 2224 (s), 2114 (s), 1101 (s).

Example 8: Preparation of Pt.SUB.2.Cu Complex [Pt.SUB.2.Cu(-Dpmp).SUB.2.(CCC.SUB.6.H.SUB.5.F-4).SUB.4.](ClO.SUB.4.) (Complex 8)

[0067] The preparation method was similar to that in Example 1, except that Pt(PPh.sub.3).sub.2(CCC.sub.6H.sub.5).sub.2 was replaced by Pt(PPh.sub.3).sub.2(CCC.sub.6H.sub.5F-4).sub.2, and [Au(tht).sub.2](ClO.sub.4) was replaced by [Cu(MeCN).sub.4](ClO.sub.4).

[0068] Yield: 75%. Elemental analysis C.sub.96H.sub.74ClCuF.sub.4O.sub.4P.sub.6Pt.sub.2, calculated: C, 56.45; H, 3.65. Found: C, 56.17; H, 3.68. HRMS m/z (%): 1942.2743 (100) [M-ClO.sub.4].sup.+. Calculated: 1942.2750. .sup.1H-NMR (d-DMSO, ppm): 8.15-8.02 (m, 4H), 7.93-7.79 (m, 8H), 7.60-7.35 (m, 14H), 7.35-7.20 (m, 12H), 7.15-6.99 (m, 12H), 6.65 (t, 4H, J=8.94 Hz), 6.48 (t, 4H, J=8.88 Hz), 6.26 (dd, 4H, J.sub.1=8.68 Hz, J.sub.2=5.64 Hz), 5.89 (dd, 4H, J.sub.1=8.78 Hz, J.sub.2=5.66 Hz), 4.41-4.20 (m, 4H), 3.78-3.60 (m, 4H). .sup.31P-NMR (d-DMSO, ppm): 11.2 (m, 4P, J.sub.PP=37.0 Hz, J.sub.PtP=2554 Hz), 12.41 (m, 2P, J.sub.PP=39.7 Hz), IR (KBr, cm.sup.1): 2114 (w), 1100 (s).

Example 9: Preparation of Pt.SUB.2.Cu Complex [Pt.SUB.2.Cu(-Dpmp).SUB.2.(CCC.SUB.6.H.SUB.2.F.SUB.3.-2,4,6).SUB.4.](ClO.SUB.4.) (Complex 9)

[0069] The preparation method was similar to that in Example 1, except that Pt(PPh.sub.3).sub.2(CCC.sub.6H.sub.5).sub.2 was replaced by Pt(PPh.sub.3).sub.2(CCC.sub.6F.sub.3-2,4,6).sub.2, and [Au(tht).sub.2](ClO.sub.4) was replaced by [Cu(MeCN).sub.4](ClO.sub.4).

[0070] Yield: 79%. Elemental analysis C.sub.96H.sub.66ClCuF.sub.12O.sub.4P.sub.6Pt.sub.2, calculated: C, 52.73; H, 3.04. Found: C, 52.32; H, 3.11. HRMS m/z (%): 2086.1989 (100) [M-ClO.sub.4].sup.+. Calculated: 2086.1996. .sup.1H-NMR (d-DMSO, ppm): 8.00-7.89 (m, 4H), 7.89-7.77 (m, 8H), 7.53-7.31 (m, 14H), 7.15 (q, 8H, J=6.36), 7.09-6.94 (m, 8H), 6.83 (t, 12H, J=7.94), 6.65 (t, 4H, J=8.42), 4.60-4.37 (m, 4H), 3.88-3.74 (m, 4H). .sup.31P-NMR (d-DMSO, ppm): 9.38 (m, 4P, J.sub.PP=35.4 Hz, J.sub.PtP=2547 Hz), 10.4 (m, 2P, J.sub.PP=37.9 Hz), IR (KBr, cm.sup.1): 2119 (w), 1101 (s).

Example 10: Preparation of Pt.SUB.2.Cu Complex [Pt.SUB.2.Cu(-Dpmp).SUB.2.(CCC.SUB.6.F.SUB.5.).SUB.4.](ClO.SUB.4.) (Complex 10)

[0071] The preparation method was similar to that in Example 1, except that Pt(PPh.sub.3).sub.2(CCC.sub.6H.sub.5).sub.2 was replaced by Pt(PPh.sub.3).sub.2(CCC.sub.6F.sub.5), and [Au(tht).sub.2](ClO.sub.4) was replaced by [Cu(MeCN).sub.4](ClO.sub.4).

[0072] Yield: 74%. Elemental analysis C.sub.96H.sub.58ClCuF.sub.20O.sub.4P.sub.6Pt.sub.2, calculated: C, 49.48; H, 2.51. Found: C, 49.32; H, 2.66. HRMS m/z (%): 2230.1259 (100) [M-ClO.sub.4].sup.+. Calculated: 2230.1242. .sup.1H-NMR (d-DMSO, ppm): 8.04-7.95 (m, 4H), 7.94-7.81 (m, 8H), 7.60-7.32 (m, 14H), 7.17-7.00 (m, 16H), 7.93-6.85 (m, 8H), 4.79-4.54 (m, 4H), 3.88-3.68 (m, 4H). .sup.31P-NMR (d-DMSO, ppm): 10.0 (m, 4P, J.sub.PP=35.5 Hz, J.sub.PtP=2483 Hz), 9.65 (m, 2P, J.sub.PP=37.6 Hz), IR (KBr, cm.sup.1): 2130 (w), 1101 (s).

Example 11: Photochromic Performance Test of Complexes 1-5

[0073] The excitation spectra, emission spectra, luminescence lifetimes and luminescence quantum yields of complexes 1-5 prepared in Example 1, 2, 3, 4, 5 in different states were measured on Edinburgh FLS920 fluorescence spectrometer, respectively. The luminescence quantum yields of the samples were determined by using a 142-mm-diameter integrating sphere. The detailed results were shown in Table 1.

TABLE-US-00001 TABLE 1 Photochromic performance data of the phosphorescent complexes 1-5 of the present invention CH.sub.2Cl.sub.2 solution.sup.(a) Solid powder.sup.(b) PMMA thin film.sup.(c) .sub.em .sub.em .sub.em .sub.em .sub.em .sub.em .sub.em .sub.em .sub.em Complex [nm] [s] [%] [nm] [s] [%] [nm] [s] [%] 1 494 1.19 0.20 550 0.46 11.9 542 3.12 30.9 2 506 0.93 <0.1 511 0.10 4.00 517 1.35 3.78 3 602 1.82 <0.1 513 1.07 0.86 506 8.60 4.80 4 606 2.36 <0.1 502 0.52 0.50 489 6.32 11.47 5 590 1.94 <0.1 500 0.87 1.30 503 8.41 2.79 .sup.(a)deoxygenated dichloromethane solution with a concentration of 1 10.sup.5 mol/L, .sup.(b)crystalline sample obtained by diffusion of dichloromethane and n-hexane and removing the solvent, .sup.(c)doped PMMA film with 3% mass fraction (complex 3%).

[0074] It can be seen from the results in Table 1 that the complexes prepared in Examples 1-5 all present phosphorescence emission, and the color distribution of the emitted light of the complexes is relatively broad from blue-green to orange-red, therefore the complexes as photochromic materials can be used in the fields of displays, lighting, sensors, and biomarkers.

Example 12: Photochromic Performance Test of Complexes 3-10

[0075] Complexes 3-10 in Examples 3-10 had sensitive photochromic properties. Among them, with complex 5 as an example, after UV irradiation for a few seconds with wavelengths of 200-400 nm, both dilute solution and PMMA (polymethylmethacrylate) doped film presented significant photochromic properties. The colors of complexes in Examples 3-8 changed from colorless to red color, and the colors of complexes in Example 9 and 10 changed from light yellow to green color. The absorption spectral changes before and after UV irradiation of complexes were measured on Perkin Elmer lambda 35 UV/Vis absorption spectrometer, respectively. The UV absorption spectra of complex 5 were shown in FIG. 1. FIG. 1 showed that after the sample of complex 5 in the solution state was placed under UV irradiation for about 10 seconds, an obvious absorption peak appeared at 550 nm. And after stopping UV irradiation, the absorption peak turned reversibly to the initial state immediately, as shown in FIG. 2, it returned to the initial state after stopping irradiation for 150 seconds. The fatigue test was carried out for the color change phenomenon of complex 5, as shown in FIG. 3. The absorbance of the dichloromethane solution of complex 5 after UV irradiation at 365 nm for 20 seconds and the absorbance at 550 nm after stopping irradiation for 150 seconds were measured, respectively. After repeated cycles, the absorbance of complex 5 at 550 nm did not decline. The .sup.1H NMR spectra of complex 5 in d-DMSO did not change significantly by comparing the .sup.1H NMR spectra before and after UV irradiation for 10 hours at 365 nm (as shown in FIG. 4), which indicated that the complex was not decomposed after a long period of UV irradiation to exhibit excellent photochemical stability.

TABLE-US-00002 TABLE 2 Photochromic performance data of the complexes 3-10 of the present invention (UV-visible absorption spectra) UV Self-recovery lifetime for Complex irradiation .sub.abs/nm (/dm.sup.3 mol.sup.1 cm.sup.1) the color change .sup.(a) 3 before 261(60300), 380(14027), 546(56) 8.9 seconds after 261(60353), 380(12972), 546(580) 4 before 263(61400), 382(31050), 541(175) 7.1 seconds after 263(60565), 382(30065), 541(452) 5 before 270(63015), 378(35440), 540(493) 35.2 seconds after 270(65316), 378(22836), 540(9655) 6 before 267(58600), 356(13500), 542(118) 536.1 seconds after 267(58420), 356(11202), 542(875) 7 before 304(96731), 370(57820), 545(127) 70.6 seconds after 304(43269), 370(15270), 545(4099) 8 before 257(74138), 382(35999), 563(158) 33.0 seconds after 257(74460), 382(34599), 563(3083) 9 before 358(32128), 376(27276), 462(904), 56.3 minutes 600(176) after 358(12141), 376(11484), 462(28235), 600(5823) 10 before 351(30736), 384(23656), 464(893), 118.8 minutes 597(144) after 351(11351), 377(10058), 464(23033), 597(4577) .sup.(a) Self-recovery lifetime for the color change was the time required for a absorbance (i.e. the maximum absorbance A) at a new maximum wavelength absorption peak, which is generated by the complex after 1 minute of irradiation with 365 nm ultraviolet light, decay to 1/e of the maximum absorbance A (A is the maximum absorbance at the maximum wavelength after irradiation, and e is the natural logarithm).

[0076] It can be seen from the results in Table 2 that complexes 3-10 of the invention are colorless or light yellow solutions in dichloromethane, but their absorption spectra change greatly after ultraviolet irradiation, and most notably, new absorption peaks appear in the range of 500-600 nm, resulting that their absorption colors change significantly and a photochromic response occurs. In addition, different substituents of the complexes can also adjust the response lifetime of the color change. It can be seen from Table 2 that for the metal complexes 3-10 with various organic substituents, broad absorption bands rapidly appear in the visible region after ultraviolet irradiation, and the maximum absorption peaks appear at a value of 540-600 nm, resulting that the colors of the solutions change from colorless or light yellow to green or red immediately, indicating that the complexes 3-10 exhibit very sensitive photochromic properties. However, the colors of the solutions gradually fade after stopping UV irradiation, indicating that the metastable state of green or red can reversibly return to the initial state of colorless or light yellow. It can also be seen from Table 2 that the time or speed required to recover from green or red to the colorless state is different, because the stability of metastable states accompanied by a color change varies depending on the different substituents in the organic ligands. The more electron deficient (withdrawing) the substituents in the organic ligands, the longer it takes to recover from the metastable state of photochromic green or red to the initial state of colorless.

[0077] The present invention first reported a kind of photochromic compounds having a self-recovery function. Under UV irradiation, the compounds changed from a colorless or light color state to a dark color state rapidly; when the UV light was turned off, the dark color state gradually returned to the light color state automatically. This kind of self-recovery photochromism was of great application value in the fields of anti-counterfeiting, information encryption and decryption, product identification, etc.

[0078] The embodiments of the present invention are described above. However, the present invention is not limited to the above embodiments. Any modification, equivalent alternative, improvement, etc., falling within the spirit and scope of the present invention, are intended to be included within the scope of the present invention.