Summary of the invention
The object of the invention is to overcome above-mentioned the deficiencies in the prior art, there is provided a kind of metal organic frame based on Cu (II) ion and synthetic method thereof and application, this metal organic frame achieves visual response and the Selective recognition of different concns and different classes of negatively charged ion and repeats regeneration and use.
For realizing above technical problem, the technical solution used in the present invention is as follows:
For the synthesis of an organic ligand L for metal organic frame, its chemical name is 2,7-bis-(1-hydrogen-1,2,4-triazole)-9,9-diisoamyl fluorenes, and its chemical structural formula is:
A kind of metal organic frame Cu (II)-MOF-1 structural formula is [Cu (C
27h
32n
6)
2(CF
3sO
3)
2]
nn is the natural number of non-zero, and Cu (II)-MOF-1 crystallization, in rhombic system, belongs to pbcn spacer, node Cu (II) metal center is in the octahedral coordination environment of distortion, and octahedral coordination plane is by four triazole atom N from ligand L
occupying, is axially that two trifluoromethane sulfonic acid roots participate in coordination:
The synthetic method of described metal organic frame Cu (II)-MOF-1, comprises the steps:
Ligand L be dissolved in methylene dichloride, be dissolved in by copper triflate in methyl alcohol, through diffusion crystallisation method, obtained Cu (II)-MOF, heats 1-2h by Cu (II)-MOF, obtains Cu (II)-MOF-1 at 100-120 DEG C.
Preferably, the concentration of described ligand L in methylene dichloride is 1.0 × 10
﹣ 3-1.2 × 10
﹣ 3g/ml.
Preferably, the concentration of described copper triflate in methyl alcohol is 1.8 × 10
﹣ 3-2.0 × 10
﹣ 3g/ml.
Preferably, described diffusion crystallisation method be methyl alcohol is layered on be dissolved with ligand L dichloromethane solution above, as buffer layer, then will be dissolved with copper triflate methanol solution paving on the buffer layer, utilize the diffusion of methyl alcohol, make copper triflate and ligand L contact reacts.
Preferred further, the volume ratio of the methanol solution being dissolved with the dichloromethane solution of ligand L, methyl alcohol and being dissolved with copper triflate is 7-9:0.8-1.2:7-9.
Preferably, the time of described standing and reacting is 3-7 days, and the temperature of reaction is 20-25 DEG C.
The application of described Cu (II)-MOF-1 in ion-exchange and regeneration.
The described application of Cu (II)-MOF-1 in ion selectivity identification.
The application of Cu (II)-MOF-1 in ion-exchange and regeneration, experiment skeleton symbol is as follows:
Above-mentioned Cu (II)-MOF-1 is in the application of ion selectivity identification.Experiment skeleton symbol is as follows:
Advantageous Effects of the present invention is:
1, by the growth of design part No. nine position carbochains, the extension in metal organic frame duct, thus the thermostability adding Cu (II)-MOF-1;
2, the normal temperature solvent diffusion method that Cu (II)-MOF-1 adopts is synthesized, mild condition, economical and practical, and normal temperature diffusion process synthesis method required time is short.
3, due to negatively charged ion CF
3sO
3 -weak binding property make Cu (II) ion height exposed, this is made metal organic frame can be exchanged by different anions and makes the coordination environment change of Cu (II) center, thus show distinct colors, achieve like this different concns and the visual response of different classes of negatively charged ion and the anion-selective identification of different coordination ability and exchange realization by negatively charged ion inverse and repeat regeneration and use.
4, diffusion crystallisation method is adopted to obtain Cu (II)-MOF, relative to directly mixing advantage can obtain the crystalline structure of Cu (II)-MOF, thus the coordination environment and structure iron of BrukerSmartApexCCD single crystal diffractometer being resolved Cu (II)-MOF can be placed in.
Accompanying drawing explanation
The coordination environment figure of Fig. 1 Cu of the present invention (II)-MOF-1;
The two-dimentional packed structures figure of Fig. 2 Cu of the present invention (II)-MOF-1;
The infrared spectrum of Fig. 3 ligand L of the present invention;
The infrared spectrum of Fig. 4 Cu of the present invention (II)-MOF-1;
The TGA spectrogram of Fig. 5 Cu of the present invention (II)-MOF-1;
Fig. 6 Cu of the present invention (II)-MOF-1 is for the color corresponding figures of different anions;
Fig. 7 Cu of the present invention (II)-MOF-1 is based on the solid-state UV-Vis spectrogram of the compound after ion-exchange;
Fig. 8 Cu of the present invention (II)-MOF-1 is based on the infrared spectrum of the compound after ion-exchange;
The XPS figure of F in Fig. 9 (a) compound 2; The F of (b) compound 2
-chromatography of ions figure; C (peak position corresponding in standard specimen is F to () compound 2 chromatography of ions full figure according to this
-, Cl
-, Br
-, SO
4 2-);
The XPS figure of Cl in Figure 10 (a) compound 3; The Cl of (b) compound 3
-chromatography of ions figure; C (peak position corresponding in standard specimen is F to () compound 3 chromatography of ions full figure according to this
-, Cl
-, Br
-, SO
4 2-);
The XPS figure of Br in Figure 11 (a) compound 4; The Br of (b) compound 4
-chromatography of ions figure; C (peak position corresponding in standard specimen is F to () compound 4 chromatography of ions full figure according to this
-, Cl
-, Br
-, SO
4 2-);
The XPS figure of I in Figure 12 compound 5;
SO in Figure 13 (a) compound 6
4 2-chromatography of ions figure; B (peak position corresponding in standard specimen is F to () compound 6 intermediate ion chromatogram full figure according to this
-, Cl
-, Br
-, SO
4 2-);
The XPS figure at Cu center in Figure 14 compound 2-7;
The XPRD of Figure 15 compound 2'-7' and Compound C u (II)-MOF-1 schemes;
Figure 16 Cu of the present invention (II)-MOF-1 based on regenerate after ion-exchange infrared spectrum;
Figure 17 Cu of the present invention (II)-MOF-1 is at SCN
-with N
3 -selective recognition N in system
3 -infrared spectrum;
Figure 18 Cu of the present invention (II)-MOF-1 limits and the time of response for the Concentration Testing of negatively charged ion sensing.
Embodiment
Mode by the following examples further illustrates the present invention, but does not therefore limit the present invention among described scope of embodiments.The experimental technique of unreceipted actual conditions in the following example, conventionally selects with condition.
Embodiment 1
The synthetic route of Cu (the II)-MOF-1 of the present invention's synthesis is as follows:
1, the preparation of ligand L:
Under normal temperature, 2,7-dibromo fluorenes (9.72g, 30mmol), Tetrabutyl amonium bromide (0.08g, 0.25mmol), the bromo-2-methylbutane of 1-(10.33g, 90mmol), the NaOH solution 10mL of 50% joins in the DMSO of 130mL, ultrasonic reaction (100W) 5 hours, pours in 500mL water after reaction terminates, 1 hour is left standstill after stirring 20mins, suction filtration, filter cake with 1% NaCl solution washing, dry, obtain the violet solid 11.90g of intermediate A, productive rate 90.9%.
N
2under protection, intermediate A (3.52g, 10mmol) 1,2; 4-triazole (1,93g, 28mmol), cesium carbonate (13.03g; 40mmmol, cuprous iodide (0.762g, 4mmol) is placed in 100ml there-necked flask; 20mlDMF makes solvent, is heated to 120 DEG C, and TLC follows the tracks of; pour in 300ml water after reaction terminates, leave standstill, suction filtration; after solid dries, silica gel column chromatography (methylene dichloride: ethyl acetate=1:1), obtains yellow solid 2.3g, productive rate 70%.The IR of ligand L as shown in Figure 3.
2, the synthesis of Cu (II)-MOF-1
In test tube, 1ml methyl alcohol is slowly layered on the 8mlCH being dissolved with L (8.8mg)
2cl
2on as buffer layer, then will be dissolved with Cu (OTf)
2(15.0mg) 8mL methyl alcohol slowly spreads on the buffer layer, room temperature leaves standstill three days and obtains green bulk crystals 12.0mg, i.e. Cu (II)-MOF, heats 1.5h by Cu (II)-MOF at 110 DEG C, namely obtains Cu (the II)-MOF-1 that we need.
Or, in test tube, 0.9ml methyl alcohol is slowly layered on the 7.5mlCH being dissolved with L (8.5mg)
2cl
2on as buffer layer, then will be dissolved with Cu (OTf)
2(14.5mg) 7.8mL methyl alcohol slowly spreads on the buffer layer, 20 DEG C leave standstill 7 days and obtain green bulk crystals 11mg, i.e. Cu (II)-MOF, heats 1h by Cu (II)-MOF at 120 DEG C, namely obtains Cu (the II)-MOF-1 that we need.
Or, in test tube, 1.2ml methyl alcohol is slowly layered on the 7mlCH being dissolved with L (8.2mg)
2cl
2on as buffer layer, then will be dissolved with Cu (OTf)
2(14mg) 7.5mL methyl alcohol slowly spreads on the buffer layer, room temperature leaves standstill 5 days and obtains green bulk crystals 10mg, i.e. Cu (II)-MOF, heats 2h by Cu (II)-MOF at 100 DEG C, namely obtains Cu (the II)-MOF-1 that we need.
Obtained Cu-MOF-1 is placed on BrukerSmartApexCCD single crystal diffractometer, with MoK α radiation
with ω/θ scan mode, collect diffraction data under low temperature (123K), structural analysis is completed by ShelxtlV6.12 software package, and the first structure of title complex solves by directly sending out, and then passes through complete matrix method of least squares to F
2carry out revising the coordinate and anisotropic parameters that obtain whole non-hydrogen atom.We characterize the structure of this compound by IR and TGA, and result is shown in accompanying drawing 4 and Fig. 5 respectively.
Cu (II)-MOF-1 coordination environment as shown in Figure 1.Cu (II)-MOF-1 is in rhombic system as shown in Figure 1, belongs to pbcn spacer, takes the mode of two dimension accumulation as shown in Figure 2.Node Cu (II) metal center is in the octahedral coordination environment of distortion, and octahedral coordination plane is by four triazole atom N from ligand L
occupying, is axially that two trifluoro sulfonate radicals participate in coordination
actual crystal data are shown in Table1.
The crystallographic data of Table1Cu (II)-MOF-1
The color response of experimental example 2 pairs of different anions and sign
The each 50mg of crystal (0.0403mmol) taking Cu (the II)-MOF-1 after 6 parts of grindings is immersed in 5mL0.2MMX (KF, KCl, KBr, KI, KSCN and NaN respectively
3) solution in, Cu-MOF-1 fast response can present different colours.The sample of variable color is taken out centrifugation solvent wash respectively and drying obtains compound 2,3,4,5,6,7 under infrared lamp.The metachromasia time is respectively immediately, 5min, 1min, 1min, 3s, immediately.We have carried out the test of solid-state UV, infrared, XPS and chromatography of ions to above-mentioned 5 kinds of compounds.
The conclusion of experimental example 2 is:
Fig. 6 shows, relative to Cu (II)-MOF-1, the color of compound 2-7 there occurs change, is respectively cream-coloured, blue-greenish colour, deep green, yellow, and grass green is blackish green.Fig. 8 shows CF in compound 2-7
3sO
3 -(1251cm
-1and 1031cm
-1) peak disappearance, this anion exchange procedures of qualitative explanation is complete.There is thiocyanate ion SCN in compound 6 and compound 7 simultaneously respectively
-ion is at 2071.46cm
-1with azide anion N
3 -at 2036.74cm
-1characteristic peak, SCN is described
-and N
3 -exchange in the framework of Cu-MOF-1.
(2) show that the ion exchange ratio having exchanged rear above-claimed cpd 2-7 is all more than 95% by the calculating of Fig. 9, Figure 10, Figure 11, Figure 12, Figure 13 XPS coupled ion chromatographic data, the anion exchange procedures that quantitative analysis obtains Cu (II)-MOF-1 is more complete.
(3) Figure 14 shows relative to Cu (II)-MOF-1 and other compound in ion exchange process, and the valence state at the Cu center of compound 5 becomes+1 valency from+divalent.
Can be drawn by conclusions: Cu (the II)-MOF-1 of this invention can realize visual F
-, Cl
-, Br
-, I
-, SCN
-and N
3 -anionresin, exchange rate can reach more than 95%.
Experimental example 3 is studied based on the recycling of the negatively charged ion sensing material of anionresin
Cu (II)-MOF-1 sample 50mg (0.0403mmol) taken after 6 parts of grindings is immersed in volume 5mL respectively, concentration is that below 0.2M is containing in the solution of different anions (1mmol), the sample of variable color is taken out centrifugation solvent wash respectively and drying obtains compound 2 under infrared lamp, 3,4,5,6,7.All transfer to 2 of gained, 3,4,5,6,7 respectively in 6 small beakers, use volume 5mL, concentration is that 0.2M contains CF
3sO
3 -the solution soaking 12h of negatively charged ion (1mmol), period changes once this solution every 1-2h.By dry under infrared lamp through the compound centrifugation solvent wash of above-mentioned process, obtain compound 2 ', 3 ', 4 ', 5 ', 6 ', 7 '.And compound 2 ', 3 ', 4 ', 6 ', the solid colour of the color of 7 ' and Cu (II)-MOF-1.
The conclusion of experimental example 3:
Figure 15 and Figure 16 shows that, except compound 5 ', other several compound can be regenerated as Cu (II)-MOF-1, thus can reuse.
Experimental example 4 is about the research of Anion separation
Take the Cu after grinding (II)-MOF-1 sample 50mg (0.0403mmol) and be immersed in volume 10mL respectively, concentration is the N of 0.1M
3 -, SCN
-mixing methanol aqueous solution (N
3 -: SCN
-=1:1) mixing solutions in, soak after 6h, the sample of variable color taken out centrifugation solvent wash and drying obtains compound 8 under infrared lamp.The color of compound 8 more levels off to the blackish green of compound 7.The infrared figure of Figure 17 shows and only has N
3 -(2037cm
-1) peak, without CF
3sO
3 -(1251cm
-1and 1031cm
-1) peak and SCN
-(2052cm
-1) peak.The content that ultimate analysis records C, H, N, S in compound 8 is respectively 63.07., and 6.21,23.89,0.70, record Theoretical molecular formula CuL
2(SCN)
0.2(N
3)
1.8, thus can illustrate that Cu (II)-MOF-1 is to N
3 -and SCN
-selectivity be: N
3 ->SCN
-, and the separating effect of color response can be realized.
Experimental example 5 is based on the Concentration Testing limit research of the negatively charged ion sensing material of anionresin
Taking 10mgCu (II)-MOF-1 grinding is respectively placed in easy elution device, does drip washing test respectively, guarantee constantly to change salts solution record color transition point with the salts solution of different concns.Strength of solution is respectively 2 × 10
-1m, 2 × 10
-2m, 2 × 10
-3m, 2 × 10
-4m, 2 × 10
-5m, 2 × 10
-6m finds that Cu (II)-MOF-1 is to different negatively charged ion distinct colors response (Figure 18), within the scope of higher concentration, the time of response is very rapid, but along with the reduction of concentration, color transition point progressively postpones, the response color of same solion there will not be too big difference.
By reference to the accompanying drawings the specific embodiment of the present invention is described although above-mentioned; but not limiting the scope of the invention; one of ordinary skill in the art should be understood that; on the basis of technical scheme of the present invention, those skilled in the art do not need to pay various amendment or distortion that creative work can make still within protection scope of the present invention.