Amorphous infinite coordination polymers and their synthesis from a - - PowerPoint PPT Presentation

Amorphous infinite coordination polymers and their synthesis from a novel set of organic ligands.

Presented by Adam Kewley

Content

• Background
• Synthesis
• Characterization
• Conclusion

Metal organic frameworks (MOFs)

Framework made from single metal ions and rigid organic ligands (linkers) to make a one- two- or three-dimensional framework that can be porous.

• Chemically tailorable
• Wide range of uses brought on by the porosity

1

MOFs (cont.)

Applications:

• Catalysis
• Separation
• Storage

Industrially, commercially, and scientifically interesting.

The major disadvantage:

• Solution based behaviour

Difficult to produce industrially large quantities. Difficult to crystallize in some cases and therefore hard to characterize etc.

Infinite coordination polymers (ICPs)

A polymer created from the coordination between metal ions and multidentate ligands to create an “infinite” framework.

• Amorphous
• Can be made into stable particles by precipitation
• Good solution behaviour
• Can encapsulate other species

2

Synthesis: Ligands

“L1”

• Reflux both reactants in DMF, filter, wash with DMF, and

recrystallize from DMF/EtOH.

• Characterized by 13C-NMR & single-crystal XRD.

Synthesis: Ligands

R=15% L1 (MeCN)

Synthesis: Ligands

“L1” “L3”

• Refluxed L1 in acetic acid, evaporated, precipitated the resulting
• il, recrystallized in water.
• Characterized by 13C, and FTIR

Synthesis: Ligands

“L3”

• Reactants refluxed in THF, filtered, THF washed, recrystallized

(CHCl3/EtOH).

• Characterized by ES-MS, 1H-NMR, Elemental analysis

Synthesis: Ligands

R=10% L3 3

Synthesis: ICPs

• Stir the metal salt and ligand in solution, centrifuge, decant, dry

(vacuum/N2)

• Stable, dispersible, particles
• Characterized by FTIR, single-crystal XRD, and AFM

ICPs: Characterization

Assignment Literature value4 (unsubst.) Uncoordinated L1 Metal coordinated CoII CoII

(ref)

CuII CuII

(ref)

MnII MnII

(ref)

ZnII ZnII

(ref)

C=O str. N/A 1644 1621 N/A 1634 N/A 1622 N/A 1632 N/A Ring str. 1509 1474 1465 1527 1490 1533 1465 1524 1489 1531 Ring str. 1486 1368 1404 1498 1404 1507 1403 1495 1401 1506 Ring str. 1359 1345 1363 1370 1384 1374 1362 1368 1384 1372 Ring str. 1323 1316 1337 1325 1342 1333 1337 1323 1340 1330 Assignment Literature value4 (unsubst.) Uncoordinated L2 Metal Coordinated CoII CoII

(ref)

CuII CuII

(ref)

MnII MnII

(ref)

ZnII ZnII

(ref)

C=O str. N/A 1654 1663 N/A 1662 N/A 1654 N/A 1667 N/A Ring str. 1509 1509 1522 1527 1523 1533 1519 1524 1528 1531 Ring str. 1486 1456 1456 1498 1456 1507 1455 1495 1455 1506 Ring str. 1359 1375 1384 1370 1384 1374 1384 1368 1384 1372 Ring str. 1323 1345 1342 1325 1341 1333 1341 1323 1342 1330

FTIR: L1 FTIR: L2

ICPs: Characterization

R=15% L1 ZnII ICP (MeCN)

References

R=15%

ICPs: Characterization

L1 ZnII ICP a b c

5.46A

ICPs: Characterization

• All spherical, aggregates
• Varying particle sizes for each reaction (3-45nm sizes)
• Possible solvent and temperature dependence observed (growth
• mech. considerations)

Growth mech

5

Conclusions

Experimentally

• Ligand synthesis appeared to be successful
• The resulting ICP particles appeared to be composed of coordinated

metal-ligand compound

• XRD shown a potentially interesting MOF structure

Overall

• ICPs have a large amount of industrially applicable potential
• Some hurdles in synthesis, mechanism to overcome

References

1 Mohamed Eddaoudi, David B. Moler, Hailian Li, Banglin Chen, Theresa

• M. Reineke, Michael O'Keeffe, and Omar M. Yaghi, J. Am. Chem. Soc.

2007, 34, 319

2 Champness, N. R. Angew. Chem.-Int. Edit. 2009, 48, 2274 3 V. J. Richards and N. Champness, previous research on the ligands 4 Carlson, R. H.; Brown, T. L. Inorg. Chem. 1966, 5, 268. 5 Spokoyny, A. M.; Kim, D.; Sumrein, A.; Mirkin, C. A. Chem. Soc. Rev.

2009, 38, 1218.