Synthesis of MOFs

Abstract

The present invention relates to the synthesis of a variety of metal organic frameworks (MOFs) using low temperature and solvents which are considered to be not particularly harmful to the environment. There is also provided novel MOFs which may be made by the desired processes.

Claims

1. A method of synthesizing a metal organic framework (MOF) of the form of M.sub.x(2,5-dihyroxyterephthalate (DHTP)).sub.y (OH).sub.v(H.sub.2O).sub.w, wherein; M is a metal or metals; and x is in a range from 1-10, y is in a range from 0.1-3, v is in a range from 0-2 and w is in a range from 0-14; the method comprising the step of providing a salt of DHTP acid or an aqueous solution thereof; and mixing the DHTP acid or an aqueous solution thereof with a water/alcohol solution in a range of 3-100 water/alcohol, of a metal salt/source, wherein the metal salt/source to the salt of DHTP acid is in the range 1-15, at a temperature between 0° C. and 100° C. at atmospheric pressure for 30 minutes to 6 hours, to thereby obtain said MOF.

2. The method according to claim 1, comprising providing a water soluble salt of DHTP.

3. The method according to claim 1, wherein M is one or more metals selected from the group consisting of Zn, Ni, Mn, Mg, Ag, Cu, and Na.

4. The method according to claim 1, wherein the metal organic framework is in the form of M.sub.2M′.sub.z(DHTP) (H.sub.2O).sub.2.qH.sub.2O, wherein q is in a range from 0-12, z is in a range from 0-8; and M is one or more metals selected from the group consisting of Zn, Ni, Mn, Mg, Ag, Cu, and Na, and M′ is a further metal selected from the group consisting of Zn, Ni, Mn, Mg, Ag, Cu, and Na.

5. The method according to claim 1, wherein the salt of DHTP or an aqueous solution thereof in the providing step is prepared by combining a conjugate acid or salt of DHTP and a base.

6. The method according to claim 5, wherein DHTP or an aqueous solution thereof in the providing step is prepared by adding a solution or suspension of the conjugate acid or salt of DHTP to a sodium hydroxide solution, to thereby provide an aqueous solution of a salt of DHTP.

7. The method according to claim 1, comprising providing an aqueous solution of a salt of DHTP, and vigorously mixing the aqueous solution with the water/alcohol solution of the metal salt.

8. The method according to claim 1, comprising providing a water soluble salt of DHTP, and vigorously mixing the water soluble salt of DHTP, with the water-alcohol solution of the metal salt, and optionally a co-solvent directly in a single vessel.

9. The method according to claim 1, wherein the metal to DHTP linker molar ratio M/L is in a range from 1-5.

10. The method according to claim 1, wherein the temperature is within a range selected from the group consisting of between 10° C. and 80° C.; between 15° C. and 65° C.; and between 20° C. and 55° C.

11. The method according to claim 1 wherein the metal salt/source ratio to the salt of DHTP acid is in the range 2-4.

12. The method according to claim 1 wherein the alcohol is ethanol or isopropanol.

13. The method according to claim 1, which excludes the use of THF, DMF, DMSO, or other non-alcoholic solvents.

14. The method according to claim 4, wherein the MOF is of the form Zn.sub.xNi.sub.yNa.sub.z(DHTP)(H.sub.2O).sub.2.qH.sub.2O, where the values of x+y+z=2 or x+y=2, z=0-8 and q=0-12.

Description

DESCRIPTION OF THE DRAWINGS

(1) The invention will now be described with reference to the following drawings in which:

(2) FIG. 1 shows XRD data for products prepared from Zn acetate with different co-solvents. The presence of an impurity phase is evident when no co-solvent is used.

(3) FIG. 2 shows XRD data for products prepared from Zn chloride with different co-solvents. The presence of an impurity phase is evident in all samples.

(4) FIG. 3 shows XRD data for products prepared from Zn nitrate with different co-solvents. The presence of an impurity phase is evident in all samples.

(5) FIG. 4 shows SEM images of Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g.hH.sub.2O prepared from reaction mixtures containing different Zn/linker (Zn/L) and water/ethanol (W/E) ratios. Top-left Zn/L 1, W/E 94; middle Zn/L 4.2 W/E 94; right Zn/L 2.6 W/E 9.7. Bottom-left Zn/L 1 W/E 3.5; right Zn/L 4.2 W/E 3.5.

(6) FIG. 5 shows NO release profiles for Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g.hH.sub.2O synthesised as per example 3a and with different Zn/linker and water/ethanol ratios: (a) Zn/L 1 W/E 0.3; (b) Zn/L 1, W/E 94; (c) Zn/L 4.2 W/E 3.5; (d) Zn/L 4.2 W/E 94; (e) Zn/L 2.6 W/E 9.7.

(7) FIG. 6 shows XRD patterns of Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g.hH.sub.2O synthesised as per example 3a and with different Zn/linker and water/ethanol ratios: (a) Zn/L 1, W/E 94; (b) Zn/L 1 W/E 3.5; (c) Zn/L 4.2 W/E 94; (d) Zn/L 4.2 W/E 3.5 (e) Zn/L 2.6 W/E 9.7.

(8) FIG. 7 shows XRD patterns for Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g.hH.sub.2O prepared as per example 3a (a) over 1 hr, (b) over 5 hr, (c) over 48 hr and (d) at 50 deg C. over 1 hr.

(9) FIG. 8 shows XRD patterns for Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g.hH.sub.2O prepared (a) as per example 3b, (b) as per example 3a.

(10) FIG. 9 shows XRD patterns for Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g.hH.sub.2O prepared (a) as per example 3a, (b) as per example 11a

(11) FIG. 10 shows XRD patterns of Ni.sub.yNa.sub.z(dhtp)(H.sub.2O).sub.g.hH.sub.2O synthesised as per example 4a with different reaction times as documented above. Data show that the phase does not change over time, although crystallinity may be affected.

(12) FIG. 11 shows XRD patterns for Ni.sub.yNa.sub.z(dhtp)(H.sub.2O).sub.g.hH.sub.2O synthesised as per Example 4b with 1 hr (red) and 4 hr (blue) reaction times. The data show that the same phase is obtained.

(13) FIG. 12 shows XRD patterns of MOFs with compositions Zn.sub.2Na.sub.2.8(DHTP)(H.sub.2O).sub.2.qH.sub.2O (top), Zn.sub.1.47Ni.sub.0.53Na.sub.0.27(DHTP)(H.sub.2O).sub.2.qH.sub.2O (middle) and Zn.sub.1.49Ni.sub.0.51Na.sub.2.28(DHTP)(H.sub.2O).sub.2.qH.sub.2O (bottom)

(14) FIG. 13 shows XRD patterns of MOFs with compositions Zn.sub.1.88Ni.sub.0.12Na.sub.3.22(DHTP)(H.sub.2O).sub.2.qH.sub.2O (top) and Ni.sub.2Na.sub.2.8(DHTP)(H.sub.2O).sub.2.qH.sub.2O (bottom)

(15) FIG. 14 shows XRD patterns for Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g.hH.sub.2O prepared as per example 6.

(16) FIG. 15 shows XRD patterns for Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g.hH.sub.2O prepared as per example 7 (blue), 8 (red) and 3a (dark blue)

(17) FIG. 16 shows XRD patterns for Ni.sub.yNa.sub.z(dhtp)(H.sub.2O).sub.g.hH2O synthesised as per Example 9. Red: order of addition: water, ethanol, Ni acetate, NaDHTP. Blue: order of addition—water, Ni acetate, NaDHTP, ethanol.

(18) FIG. 17a shows XRD pattern of ZnNaDHTP prepared as per example 11b;

(19) FIG. 17b shows XRD pattern of ZnNaDHTP prepared as per example 13;

(20) FIG. 18 shows XRD pattern of NiNaDHTP prepared as per example 4c;

(21) FIG. 19 shows XRD patterns of NiNaDHTP prepared as per example 15a (bottom) and 15b (top);

(22) FIG. 20 shows powder XRD patterns of the Ag-BTC MOF prepared according to examples 16 (middle), 17 (top) and 18 (bottom).

(23) FIG. 21 shows powder XRD patterns of the Ag-BTC MOF prepared according to examples 16, 19, 20 and 21 (bottom to top).

(24) FIGS. 22(a)-(c) show powder XRD pattern of the Ag-BTC MOFs prepared according to examples 22(a)-(c).

(25) FIG. 23 shows powder XRD patterns of the Ag-BTC MOF prepared according to example 23, with crystallisation periods of (top to bottom) 45 min, 2, 6, 17, 24 hr.

(26) FIG. 24 shows powder XRD patterns of the Ag-BTC MOF prepared according to examples 24 (top) and 25 (bottom).

(27) FIG. 25 shows an powder XRD pattern of the Ag-BTC MOF prepared according to example 28.

(28) FIGS. 26(a) and (b) show powder XRD patterns of the Ag-BTC MOF prepared according to examples 29 and 30, respectively.

(29) FIG. 27 shows the asymmetric unit cell of the Ag-BTC MOF.

(30) FIG. 28 shows a ball and stick representation of the Ag-BTC along the a- (top) and c-axis (bottom), respectively.

(31) FIG. 29 shows the thermogravimetric analysis of the Ag-BTC of example 16.

(32) FIG. 30 shows the thermogravimetric analysis of the Ag-BTC of example 29.

(33) FIG. 31 shows the thermogravimetric analysis of the Ag-BTC of example 30.

(34) FIG. 32 shows growth inhibition of E. coli NCTC9001.

(35) FIG. 33 shows growth inhibition of P. mirabilis NCTC11938.

(36) FIG. 34 shows growth inhibition of P. aeruginosa (Pa01).

(37) FIG. 35 shows growth inhibition of P. aeruginosa (Pa058).

(38) FIG. 36 shows growth inhibition of S. aureus (DSMZ11729).

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

Examples Relating to MOFs Containing DHTP Linkers

Preparation of sodium 2,5-dihydroxyterephthalate

Example 1

(39) 2,5-dihydroxyterephthalic acid (10 g, 50.5 mmol) was added to 1 molar aqueous sodium hydroxide solution (200 ml) with vigorous stirring. Once the acid dissolved, the sodium salt was precipitated by adding in excess of 200 ml of ethanol. The product was filtered and washed in ethanol before being refluxed in ethanol (200 ml, 80 C) for 2-3 hr. The solid was filtered hot, washed with hot ethanol and air dried.

Example 2

(40) 2,5-dihydroxyterephthalic acid (10 g, 50.5 mmol) was added to 1 molar aqueous sodium hydroxide solution (200 ml) with vigorous stirring. Once the acid dissolved, the sodium salt was recovered by evaporating off water under vacuum in a rotary evaporator. The product was refluxed in ethanol (200 ml, 80 C) for 2-3 hr, filtered hot, washed with hot ethanol and air dried.

Process 1

Example 3a: ZnNaDHTP

(41) Sodium 2,5-dihydroxyterephthalate (0.48 g, 2 mmol) was dissolved in deionised (DI) water (15 ml) and the resulting solution was added dropwise over 3-5 min to a previously prepared aqueous solution of Zn acetate dihydrate (1.141 g, 5.2 mmol, in 7.5 ml DI water and 7.5 ml ethanol) under vigorous stirring. The mixture was stirred at 20 C for 4 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

(42) TABLE-US-00001 TABLE 1 Zn source Co-solvent Phase Zn acetate — Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O + secondary phase Ethanol Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O Methanol Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O Iso-propanol Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O Zn nitrate — Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O + secondary phase Ethanol Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O + secondary phase Methanol Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O + secondary phase Iso-propanol Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O + secondary phase Zn — Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O + secondary phase chloride Ethanol Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O + secondary phase Methanol Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O + secondary phase Iso-propanol Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O + secondary phase

(43) Table 1 shows a summary of variations to Example 3a using different Zn sources and co-solvent showing that the phase purity depends on Zn source and co-solvent

(44) TABLE-US-00002 TABLE 2 Approx Water/ particle ethanol size (SEM) (mol ratio (μm) [see Zn/linker in final images in Yield (mol ratio) solution) Phase FIG. 4 ] (g) 1 94 Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O 5 0.67 1 3.5 Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O <1  0.40 2.6 94 Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O No data 0.53 2.6 9.7 Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O 5 0.48 2.6 3.5 Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O No data 0.52 4.2 94 Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O 5 0.39 4.2 3.5 Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O <1  0.16

(45) Table 2 shows summary of variations to Example 3a with different Zn/linker and water/ethanol ratios; the data show that solvent composition helps control particle size and yield

(46) TABLE-US-00003 TABLE 3 Temperature Time (deg C.) (hr) Phase Yield (g) 20 1 Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O 0.48 5 Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O 0.53 24 Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O 0.56 48 Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O 0.54 50 1 Zn.sub.xNa.sub.z(dhtp)(H.sub.2O).sub.g•hH.sub.2O 0.37

(47) Table 3 shows a summary of variations to Example 3a with different reaction temperatures.

Example 3b: ZnNaDHTP

(48) Sodium 2,5-dihydroxyterephthalate (0.48 g, 2 mmol) was dissolved in DI water (15 ml) and the resulting solution was added swiftly to a previously prepared aqueous solution of Zn acetate dihydrate (1.141 g, 5.2 mmol, in 7.5 ml DI water and 7.5 ml ethanol) under vigorous stirring. The mixture was stirred at 20 C for 4 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

Example 4a: NiNaDHTP

(49) Sodium 2,5-dihydroxyterephthalate (0.48 g, 2 mmol) was dissolved in DI water (15 ml) and the resulting solution was added dropwise over 3-5 min to a previously prepared aqueous solution of Ni acetate dihydrate (1.294 g, 5.2 mmol, in 7.5 ml DI water and 7.5 ml ethanol) under vigorous stirring. The mixture was stirred at 20 C for 7 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

(50) TABLE-US-00004 TABLE 4 Temperature Time (deg C.) (hr) Phase Yield (g) 20 1 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.34 20 2 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.42 20 4 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.46 20 7 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.52 20 18 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.58 20 24 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.61 20 28 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.58

(51) Table 4 shows a summary of variations to Example 4a with different reaction times. The data show that the formation of the Ni end-member is generally slower than that for the Zn end-member—taking approx. 20 hr to reach maximum yield at 20 C.

Example 4b: NiNaDHTP

(52) Sodium 2,5-dihydroxyterephthalate (0.48 g, 2 mmol) was dissolved in DI water (15 ml) and the resulting solution was added dropwise over 3-5 min to a previously prepared aqueous solution of Ni acetate dihydrate (1.294 g, 5.2 mmol, in 7.5 ml DI water and 7.5 ml ethanol) under vigorous stirring. The mixture was stirred at 50 C for 4 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

(53) TABLE-US-00005 TABLE 5 Temperature Time (deg C.) (hr) Phase Yield (g) 50 1 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.52 4 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.63 6 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.68

(54) Table 5 shows a summary of variations to Example 4b with different reaction times showing that the process time can be reduced to a few hours by raising the temperature slightly to 50 C.

(55) TABLE-US-00006 TABLE 6 Water/co- solvent (mol Ni/linker ratio in final (mol ratio) solution) Phase Yield (g) 1.4 9.7 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.77 2 9.7 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.62 2.6 9.7 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.68 3.2 9.7 Ni.sub.yNa.sub.z(dhtp) (H.sub.2O).sub.g•hH.sub.2O 0.50

(56) Table 6 shows a summary of variations to Example 4b with different Ni/Na linker ratios.

Example 4c: NiNaDHTP

(57) 2,5-dihydroxyterephthalic acid (2.02 g, 10.2 mmol) was added to aqueous sodium hydroxide (30 ml, 1.017M). The resulting solution was added dropwise over 15 min to a solution of Ni acetate dihydrate (5.10 g, 20.4 mmol) in DI water (30 ml). The mixture was stirred vigorously at 50 C for 6 hr before the product was recovered by filtration, washed in water (60 ml) and air dried.

Example 5: ZnNiNaDHTP

(58) Sodium 2,5-dihydroxyterephthalate (0.48 g, 2 mmol) was dissolved in DI water (15 ml) and the resulting solution was added dropwise over 3-5 min to a previously prepared aqueous solution of Ni acetate dihydrate (0.129 g, 0.52 mmol) and Zn acetate dihydrate (1.027 g, 0.47 mmol) in 7.5 ml DI water and 7.5 ml ethanol, under vigorous stirring. The mixture was stirred at 20 C for 4 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

(59) TABLE-US-00007 TABLE 7 Zn/Ni Average mol Approx particle % Composition size NO released used in of product (SEM) (mmol/g)/ reaction (EDX) (μm) time 100/0  Zn.sub.2Na.sub.2.8(DHTP)(H.sub.2O).sub.2•qH.sub.2O 5 0.05/12 hr  90/10 Zn.sub.1.88Ni.sub.0.12Na.sub.3.22(DHTP)(H.sub.2O).sub.2•qH.sub.2O 5 0.3/18 hr 80/20 Zn.sub.1.77Ni.sub.0.23Na.sub.3.93(DHTP)(H.sub.2O).sub.2•qH.sub.2O 3 70/30 Zn.sub.1.47Ni.sub.0.53Na.sub.0.27(DHTP)(H.sub.2O).sub.2•qH.sub.2O <1 0.3/45 hr 60/40 Zn.sub.1.49Ni.sub.0.51Na.sub.2.28(DHTP)(H.sub.2O).sub.2•qH.sub.2O <1 0.7/17 hr

(60) Table 7 shows a summary of variations to Example 5 showing how particle size and NO release profile can be tuned by varying the Zn/Ni ratio

Process 2

Example 6: ZnNaDHTP

(61) Zn acetate dihydrate (1.141 g, 5.2 mmol), DI water (22.5 ml), ethanol (7.5 ml) and sodium 2,5-dihydroxyterephthalate (0.48 g, 2 mmol), were mixed together. The mixture was stirred vigorously at 20 C for 4 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

Example 7: ZnNaDHTP

(62) Zn acetate dihydrate (3.5 g, 16 mmol), DI water (22.5 ml), ethanol (7.5 ml) and sodium 2,5-dihydroxyterephthalate (1.49 g, 6.2 mmol), were mixed together. The mixture was stirred vigorously at 20 C for 4 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

Example 8: ZnNaDHTP

(63) Zn acetate dihydrate (7 g, 0.032 mol), DI water (22.5 ml), ethanol (7.5 ml) and sodium 2,5-dihydroxyterephthalate (2.97 g, 0.012 mol), were mixed together. The mixture was stirred vigorously at 20 C for 4 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

Example 9: NiNaDHTP

(64) Ni acetate dihydrate (1.027 g, 0.47 mmol), DI water (22.5 ml), ethanol (7.5 ml) and sodium 2,5-dihydroxyterephthalate (0.48 g, 2 mmol), were mixed together. The mixture was stirred vigorously at 20 C for 4 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

Process 3

Example 10: ZnNaDHTP

(65) a) 2,5-dihydroxyterephthalic acid (0.51 g, 2.6 mmol) was added to aqueous sodium hydroxide (15 ml, 0.67M). A solution of Zn acetate dihydrate (1.141 g, 5.2 mmol) in DI water (7.5 ml) and ethanol (7.5 ml) was added dropwise to the resulting solution over 3-5 min with stirring. The mixture was stirred vigorously at 20 C for 4 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

(66) b) 2,5-dihydroxyterephthalic acid (0.51 g, 2.6 mmol) was added to aqueous sodium hydroxide (15 ml, 0.52M). A solution of Zn acetate dihydrate (1.141 g, 5.2 mmol) in DI water (7.5 ml) and ethanol (7.5 ml) was added dropwise to the resulting solution over 3-5 min with stirring. The mixture was stirred vigorously at 20 C for 4 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

Example 11a: ZnNaDHTP

(67) Zn acetate dihydrate solution (1.141 g, 5.2 mmol, in 7.5 ml DI water and 7.5 ml ethanol) was added dropwise over 3-5 min to a previously prepared solution of sodium 2,5-dihydroxyterephthalate (0.48 g, 2 mmol) in DI water (15 ml) under vigorous stirring. The mixture was stirred at 20 C for 4 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

Example 11b: ZnNaDHTP

(68) 2,5-dihydroxyterephthalic acid (1.03 g, 5.2 mmol) was added to aqueous sodium hydroxide (30 ml, 0.35M) and heated to 60 C. To the resulting solution was added Zn acetate dihydrate (2.96 g, 13.5 mmol) in DI water (15 ml) and ethanol (15 ml), dropwise over 25 min, with stirring. The mixture was stirred vigorously at 60 C for 4 hr before the product was recovered by filtration, washed in water (30 ml) and air dried

Example 12: ZnNaDHTP

(69) 2,5-dihydroxyterephthalic acid (0.39 g, 2 mmol), sodium hydroxide (0.16 g, 4 mmol) and then Zn acetate dihydrate (1.141 g, 5.2 mmol) was dissolved in DI water (22.5 ml) and ethanol (7.5 ml) with stirring. The mixture was stirred vigorously at 20 C for 4 hr before the product recovered by filtration, washed in water (30 ml) and air dried.

Example 13: ZnNaDTHP; Higher Concentration Synthesis

(70) 2,5-dihydroxyterephthalic acid (2.3 g, 11.8 mmol) was dissolved in aqueous sodium hydroxide (24 ml, 2M) at 60 C. A solution of Zn acetate dihydrate (8 g, 36.5 mmol) in DI water (13 ml) and ethanol (4.3 ml), also at 60 C, was added dropwise to the resulting solution over 3-5 min with stirring. The mixture was stirred vigorously at 60 C for 3 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

Example 14: NiNaDHTP

(71) 2,5-dihydroxyterephthalic acid (2.02 g, 10.2 mmol) was added to aqueous sodium hydroxide (30 ml, 1.017M). To the resulting solution Ni acetate dihydrate (5.10 g, 20.4 mmol) in DI water (30 ml) was added dropwise over 15 min. The mixture was stirred vigorously at 50 C for 6 hr before the product was recovered by filtration, washed in water (60 ml) and air dried.

Example 15: NiNaDHTP

(72) a) 2,5-dihydroxyterephthalic acid (0.51 g, 2.6 mmol) was added to aqueous sodium hydroxide (15 ml, 0.67M). A solution of Ni acetate dihydrate (1.296 g, 5.2 mmol) in DI water (15 ml) was added dropwise to the resulting solution over 3-5 min with stirring. The mixture was stirred vigorously at 50 C for 6 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

(73) b) 2,5-dihydroxyterephthalic acid (0.51 g, 2.6 mmol) was added to aqueous sodium hydroxide (15 ml, 0.52M). A solution of Ni acetate dihydrate (1.296 g, 5.2 mmol) in DI water (15 ml) was added dropwise to the resulting solution over 3-5 min with stirring. The mixture was stirred vigorously at 50 C for 6 hr before the product was recovered by filtration, washed in water (30 ml) and air dried.

(74) Examples Relating to MOFs Containing BTC Linkers

(75) Materials were prepared according to three general synthetic procedures (A)-(C) described below.

(76) Synthesis Procedure (A)

(77) A basic solution (such as aqueous sodium hydroxide, potassium hydroxide, or organic bases such as ammonia, trimethylamine, triethylamine or similar) is added to a suspension of trimesic acid in water (preferably distilled or de-ionised) until the desired pH is achieved at which the suspended trimesic acid dissolves (typically pH 7 and above, depending on the basic solution used). A solution of a metal salt is then added at the required rate under brisk stirring. The invention is not limited to a particular metal salt or salts, or solvent. For the preparation of Ag-BTC MOFs, silver nitrate in distilled water is preferred, in order to minimise use of organic solvents. On mixing of the two solutions at a temperature typically in the range 2-100° C. or 18-30° C., a precipitate is formed which is recovered after a period of time (e.g. 1 min to 2 days, or more preferably in the range 20-120 min). Precipitate is recovered by any suitable method, (e.g. filtration). In an optional purification step, the product is washed with one or more solvents (e.g. water then ethanol), and air dried. Examples 16-25 of preparing a Ag-BTC MOF by method (A) are set out below.

Example 16

(78) 1M sodium hydroxide solution was added dropwise to a suspension of trimesic acid (1.007 g, 4.8 mmol) in distilled 75 ml water to a phenolphthalein end-point (pH7). To this was added a solution of silver nitrate (3.5 equivalents) in 12.5 ml distilled water, dropwise with stirring at 20° C. After 45 min the product was recovered by filtration, washed with distilled water, then ethanol and air dried.

Example 17

(79) 1M sodium hydroxide solution was added dropwise to a suspension of trimesic acid (1.007 g, 4.8 mmol) in distilled 75 ml water to achieve pH 10. To this was added a solution of silver nitrate (3.5 equivalents) in 12.5 ml distilled water, dropwise with stirring at 20° C. After 45 min the product was recovered by filtration, washed with distilled water, then ethanol and air dried.

Example 18

(80) 1M sodium hydroxide solution was added dropwise to a suspension of trimesic acid (1.007 g, 4.8 mmol) in distilled 75 ml water to achieve pH 6. To this was added a solution of silver nitrate (3.5 equivalents) in 12.5 ml distilled water, dropwise with stirring at 20° C. After 45 min the product was recovered by filtration, washed with distilled water, then ethanol and air dried.

Example 19

(81) 1M sodium hydroxide solution was added dropwise to a suspension of trimesic acid (1.007 g, 4.8 mmol) in distilled 75 ml water to a phenolphthalein end-point. To this was added a solution of silver nitrate (3.5 equivalents) in 12.5 ml distilled water, quickly with stirring at 20° C. After 45 min the product was recovered by filtration, washed with distilled water, then ethanol and air dried.

Example 20

(82) 1M sodium hydroxide solution was added dropwise to a suspension of trimesic acid (1.007 g, 4.8 mmol) in distilled 75 ml water to a phenolphthalein end-point. This solution was added to a solution of silver nitrate (3.5 equivalents) in 12.5 ml distilled water, dropwise with stirring at 20° C. After 45 min the product was recovered by filtration, washed with distilled water, then ethanol and air dried.

Example 21

(83) 1M sodium hydroxide solution was added dropwise to a suspension of trimesic acid (1.007 g, 4.8 mmol) in distilled 75 ml water to a phenolphthalein end-point. This solution was added to a solution of silver nitrate (3.5 equivalents) in 12.5 ml distilled water, quickly with stirring at 20° C. After 45 min the product was recovered by filtration, washed with distilled water, then ethanol and air dried.

Example 22a

(84) 1M sodium hydroxide solution was added dropwise to a suspension of trimesic acid (1.007 g, 4.8 mmol) in distilled 75 ml water to a phenolphthalein end-point. To this was added a solution of silver nitrate (3.5 equivalents) in 12.5 ml distilled water, dropwise with stirring at 60° C. After 45 min the product was recovered by filtration, washed with distilled water, then ethanol and air dried.

Example 22b

(85) Trimesic acid (5 g, 23.8 mmol) was dissolved in aqueous sodium hydroxide (71.4 ml, 1M) under reflux. Once dissolved, the solution was cooled to 60° C. before a solution of silver nitrate (12 g, 70.6 mmol) in water (100 ml) was added. After stirring at 60° C. for 4 hr, the product was recovered by filtration, washed with distilled water, then ethanol and air dried. Approximate product composition of material synthesised in this manner was found to be in the range Ag.sub.2-4(BTC).sub.0.5-2. 1-3H.sub.2O (as determined from single crystal XRD and TGA studies). Powder XRD data (FIG. 22(b)) and single crystal XRD data indicate that the material is a new phase and differs from the materials synthesised at a lower temperature (examples 22a and 22c).

Example 22c

(86) Trimesic acid (5 g, 23.8 mmol) was dissolved in aqueous sodium hydroxide (71.4 ml, 1M) under reflux. Once dissolved, the solution was cooled to room temperature before a solution of silver nitrate (12 g, 70.6 mmol) in water (100 ml) was added. After stirring at room temperature for 4 hr, the product was recovered by filtration, washed with distilled water, then ethanol and air dried.

Example 23

(87) 1M sodium hydroxide solution was added dropwise to a suspension of trimesic acid (1.007 g, 4.8 mmol) in distilled 75 ml water to a phenolphthalein end-point. To this was added a solution of silver nitrate (3.5 equivalents) in 12.5 ml distilled water, dropwise with stirring at 20° C. After 20 min, 1 hr, 5 hr. 16 hr and 24 hr the product was recovered by filtration, washed with distilled water, then ethanol and air dried.

Example 24. 1:14

(88) 1M sodium hydroxide solution was added dropwise to a suspension of trimesic acid (0.503 g, 2.4 mmol) in distilled 75 ml water to a phenolphthalein end-point. To this was added a solution of silver nitrate (14 equivalents) in 50 ml distilled water, dropwise with stirring at 20° C. After 45 min the product was recovered by filtration, washed with distilled water, then ethanol and air dried.

Example 25. 1:1

(89) 1M sodium hydroxide solution was added dropwise to a suspension of trimesic acid (1.131 g, 5.4 mmol) in distilled 75 ml water to a phenolphthalein end-point. To this was added a solution of silver nitrate (1 equivalent) in 12.5 ml distilled water, dropwise with stirring at 20° C. After 45 min the product was recovered by filtration, washed with distilled water, then ethanol and air dried.

Example 26

(90) Trimesic acid (5 g, 23.8 mmol) was dissolved in NaOH (1M, 74.1 mL) and water (218.8 mL) at 30° C. Once dissolved, the pH was adjusted to 7 using nitric acid before silver nitrate (12 g, 70.6 mmol) in water (100 mL) was charged rapidly to the flask. After stirring at 30° C. for 2.5 hr, the product was recovered by filtration, washed with distilled water, then ethanol and air dried.

Example 27. [Slower Addition Rate]

(91) Trimesic acid (5 g, 23.8 mmol) was dissolved in NaOH (1M, 74.1 mL) and water (218.8 mL) at 30° C. Once dissolved, the pH was adjusted to 7 using nitric acid before silver nitrate (12 g, 70.6 mmol) in water (100 mL) was charged over 10 min to the flask. After stirring at 30° C. for 2.5 hr, the product was recovered by filtration, washed with distilled water, then ethanol and air dried.

(92) XRPD data indicate that examples 26 and 27 produced the same phase as examples 16, 19, 20, 21, 22(a), 22(c), 23, 24, 25, 29 and 30.

(93) Synthesis Procedure (A′)

(94) A MOF synthesised according to procedure (A) is dried and then heated in water with stirring. The resulting MOF is then coiled, filtered and dried.

Example 28

(95) 10 g of the dried product from example 22(b) was heated in water at 70° C., with stirring, for 12 hr before being cooled, filtered and dried.

(96) Approximate product composition of material synthesised in this manner was found to be in the range Ag.sub.2-4(BTC).sub.0.5-2. 1-2H.sub.2O (as determined from single crystal XRD and TGA studies). Powder XRD data (FIG. 25) and single crystal XRD data indicate that the material is a new phase and differs from the materials synthesised in examples 22(a)-(c).

(97) Synthesis Procedure (B)

(98) A suspension of trimesic acid in water (preferably distilled or deionised) is neutralised with base (for example, but not limited to, sodium hydroxide) until the desired pH is sufficiently high for the trimesic acid to dissolve. Once the acid has dissolved, the water is evaporated to leave a trimesate salt residue, which is purified by refluxing in a suitable solvent (e.g. ethanol). The salt is then recovered by an appropriate means such as filtration.

(99) An aqueous solution of the trimesate salt is then prepared and a solution of a metal salt in an appropriate solvent (e.g. silver nitrate in water) is added, as described above in relation to method A, and the resulting MOF recovered and washed with water and ethanol. Example 26 of preparing a Ag-BTC MOF by method (B) is set out below.

Example 29

(100) 3.5 equiv of sodium hydroxide was added to a suspension of 1 equiv trimesic acid in distilled water with stirring. The trimesic acid slowly dissolved and the solution stirred for a further 30 minutes and the water evaporated. The residue was refluxed in ethanol for 30 minutes and recovered by filtration and air dried.

(101) A solution of silver nitrate (3 equivalents) in distilled water was added dropwise to an aqueous solution of the sodium salt of trimesic acid with stirring. The product was recovered by filtration, washed with distilled water, then ethanol and air dried.

(102) Synthesis Procedure (C)

(103) A single crystal Ag-BTC MOF sample was prepared as follows:

Example 30

(104) A solution of the sodium salt of trimesic acid (69.0 mg, 0.2 mmol) in distilled water (5 ml) was placed into the bottom of a test tube, to which distilled water (5 ml) was carefully layered on top and then a solution of silver nitrate (102.0 mg, 0.6 mmol, 3 equiv.) in distilled water (5 mL). The resultant layered solution was placed in the dark to crystallise for 4 days. The product was recovered by filtration, washed with distilled water, then ethanol and air dried. Small single crystals were visible.

Experimental

Powder X-Ray Diffraction

(105) Data were collected on a Panalytical Empyrean diffractometer operating Cu Kα.sub.1 radiation monochromated with a curved Ge (111) crystal in reflectance mode.

(106) Single Crystal X-Ray Diffraction

(107) Data were collected on beamline 11.3.1 at the Advanced Light Source, Berkeley, Calif. The structure was solved by direct methods (SHELXS97) and refined by full-matrix least-squares analysis (SHELXL-97).

(108) Thermal Analysis

(109) Data were collected on a TA Instruments SDT 2960. Samples were heated in an alumina crucible at a rate of 10° C. min.sup.−1 to a maximum temperature of 900° C. in a flowing atmosphere of air.

(110) Elemental Analysis

(111) Data were collected on a Carlo Erba Flash 2000 Organic Elemental Analyser.

(112) Antimicrobial Susceptibility

(113) Antimicrobial susceptibility testing to determine the growth inhibition by the test items was carried out using modifications of the following Clinical and Laboratory Standards Institute (CLSI) Approved Standards:

(114) Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria that Grow Aerobically (M07-A8)

(115) Antimicrobial susceptibility testing using the above CLSI Approved Standards requires test antimicrobial materials to be in an aqueous solution. As MOFs are solid disks it was not possible to follow these methods precisely. The MOFs were not optically transparent and therefore did not permit kinetic analysis of microbial growth by changes in optical density. Therefore, the above CLSI protocol was adapted to monitor microbial metabolic activity using 10% (v/v) resazurin (Alamar blue; a cell viability indicator) which detected growth by changes in fluorescence rather than optical density. Changes in fluorescence were determined using a BioTek Synergy HT Multi-Mode Microplate Reader.

(116) The following bacterial strains were tested to determine antibacterial activity E. coli NCTC9001 P. mirabilis NCTC11938 S. aureus DSMZ11729 P. aeruginosa Pa01 P. aeruginosa Pa058

(117) Analytical Data

(118) Powder X-Ray Diffraction

(119) Powder X-ray diffraction data (FIGS. 20-26) show that the Ag-BTC materials made by the procedures A-C are new phases which differ (discussed above) from Ag BTC MOFs described in the literature. In addition, there are no similar materials present within the International Centre for Diffraction Data, Powder Diffraction File (“ICDD PDF”) database. These data also confirm that the materials prepared by the different synthesis methods of procedures A-C contain the same phases.

(120) Example 22a was prepared at an elevated temperature of 60° C. The contrast of the corresponding powder XRD pattern (FIG. 22(a) to the patters shown in FIG. 20, for example, demonstrate the temperature sensitivity of the synthesis. This is further demonstrated by the differences between each of examples 22(a)-(c).

(121) The powder diffraction pattern of example 30 differs from that of the previous examples by the addition of intense diffractions peaks (quantity in brackets) at approximately 9.4, 12.3, 18.6 (2), 28.2 (2), 36.8 (multiple) and 37.6 (2) ° 20. These peaks result from an impurity phase. Peaks common to samples 16-26 are also present.

(122) Single Crystal X-Ray Diffraction

(123) The material of example 27 was found to crystallise in the triclinic space group P-1, details of the crystal structure and refinement information are presented in Table 1.

(124) TABLE-US-00008 TABLE 1 Crystal data and structure refinement for AgBTC. Identification code AgBTC Empirical formula Ag.sub.14(C.sub.9H.sub.3O.sub.6).sub.4(OH).sub.2 Formula weight 2372.65 Temperature 150(2) K Wavelength 0.77490 Å Crystal system, space group Triclinic, P-1 Unit cell dimensions a = 8.707(2) Å α = 102.559(4)° b = 13.950(3) Å β = 99.157(3)° c = 19.756(5) Å γ = 100.934(4)° Volume 2249.0(9) Å.sup.3 Z, Calculated density 2, 3.504 Mg/m.sup.3 Absorption coefficient 6.039 mm.sup.−1 F(000) 2192 Crystal size 0.01 × 0.01 × 0.05 mm Theta range for data collection 2.79 to 34.57° Limiting indices −12 <= h <= 12, −20 <= k <= 19, −28 <= I <= 28 Reflections collected/unique 32843/13747 [R(int) = 0.0685] Completeness to theta = 34.57 92.90% Refinement method Full-matrix least-squares on F.sup.2 Data/restraints/parameters 13747/140/365 Goodness-of-fit on F.sup.2   1.166 Final R indices [I > 2sigma(I)] R.sub.1 = 0.2468, wR.sub.2 = 0.5677 R indices (all data) R.sub.1 = 0.2916, wR.sub.2 = 0.5854 Largest diff. peak and hole 9.820 and −22.325e .Math. Å.sup.−3

(125) FIG. 27 shows the asymmetric unit contains fourteen silver (I) ions, four molecules of trimesate and two hydroxyls to give an overall chemical formula of Ag.sub.14(C.sub.9H.sub.3O.sub.6).sub.4(OH).sub.2. This produces a three-dimensional connected material with small pores along the a-axis that contain protruding hydroxyl groups (FIG. 28).

(126) Chemical Composition

(127) TABLE-US-00009 TABLE 2 Results of CHN elemental analysis. C (wt %) H (wt %) N (wt %) (1) (2) (1) (2) (1) (2) Example 1 18.83 18.97 1.25 1.17 <0.1 <0.1 Example 2 19.32 19.19 1.07 1.16 <0.1 <0.1 Example 3 18.95 19.05 1.08 1.14 <0.1 <0.1 Theoretical 18.22 0.59 0.00

(128) The refined structure obtained from single crystal X-ray diffraction is also consistent with the results obtained from the CHN elemental analysis (Table 2). However, there are differences in the thermogravimetric analysis (TGA), FIGS. 29-31, which explain the small discrepancies from the CHN elemental analysis. The TGA data infer that there are volatiles present within the small pores of the material (water or ethanol from the synthesis method) and this could be contributing to the differences observed in both the TGA and elemental analysis.

(129) Thermal analysis revealed a mass loss between ambient to −120° C. ranging from 4.09-9.42 wt % and a further mass loss between 120° C. and 400° C. ranging from 34.90-37.39 wt %. The first mass loss is attributed to volatiles (water and/or ethanol) and the second to trimesate with a solid residue ranging from 55.39-61.72 wt %. The discrepancies could be due to the different synthetic routes and therefore represents a window of chemical composition for this novel material.

(130) Microbial Susceptibility Testing

(131) E. coli (NCTC9001).

(132) The results in FIG. 32 demonstrate that the above material inhibits metabolic activity of E. coli (NCTC9001) after 20 hours incubation at 37° C. under aerobic conditions.

(133) P. mirabilis (NCTC11938).

(134) The results in FIG. 14 demonstrate that the above material inhibits the metabolic activity of P. mirabilis (NCTC11938) after 20 hours incubation at 37° C. under aerobic conditions.

(135) P. aeruginosa (Pa01).

(136) The results in FIG. 34 demonstrate that the above material inhibits the metabolic activity of P. aeruginosa (Pa01) after 20 hours incubation at 37° C. under aerobic conditions.

(137) P. aeruginosa (Pa058).

(138) The results in FIG. 35 demonstrate that the above material inhibits the metabolic activity of P. aeruginosa (Pa058) after 20 hours incubation at 37° C. under aerobic conditions.

(139) S. aureus (DSMZ11729).

(140) The results in FIG. 36 demonstrate that the above material inhibits the metabolic activity of S. aureus (DSMZ11729) after 20 hours incubation at 37° C. under aerobic conditions.

(141) These data show that the novel silver trimesate MOF material of the present invention shows excellent antibacterial activity towards several strains of bacterium. It is proposed that the antibacterial properties may be related to the comparatively high silver content (in relation to previously reported Ag-MOFs).

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