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THE ROLE OF CRYSTALLINE ENVIRONMENT IN THE INTRA MOLECULAR REACTIONS

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  1. THE ROLE OF CRYSTALLINE ENVIRONMENT IN THE INTRAMOLECULAR REACTIONS Elena V. Boldyreva REC-008 MDEST Novosibirsk State University & Institute of Solid State Chemistry RAS boldyrev@nsu.ru

  2.  Introduction Effects of the environment  Response of the environment Conclusions

  3. Introduction Effects of the environment  Response of the environment Conclusions

  4. Supramolecular systems Supramolecular assemblies Supermolecules Associates (dimers) Very large molecules (proteins, DNA, RNA) solutions crystals Associates of supermolecules Supermolecules (Multisubunit proteins, nucleoproteids) Supramolecular assemblies of supermolecules (protein crystals)

  5. Supramolecular systems Supramolecular assemblies Supermolecules Associates (dimers) Very large molecules (proteins, DNA, RNA) solutions crystals Associates of supermolecules Supermolecules (Multisubunit proteins, nucleoproteids) Supramolecular assemblies of supermolecules (protein crystals)

  6. Molecular / ionic-molecular crystals • Van der Waals interactions • Hydrogen bonds • Other specific interactions

  7. The effect of intermolecular interactions on the properties of assemblies on the structures of assemblies supramolecular synthesis  crystal engineering  statistical analyses of databases  prediction of crystal structures physical properties chemical reactivity important for practice  intermolecular potentials  molecular  crystal  kinetics  reaction selectivity  effects of  reaction type structures of product temperature wavelength pressure response to external actions (homogeneous/heterogeneous, single-crystal  single-crystal)  cooperative effects

  8. The effect of intermolecular interactions on the properties of assemblies on the structures of assemblies supramolecular synthesis  crystal engineering  statistical analyses of databases  prediction of crystal structures physical properties chemical reactivity important for practice  intermolecular potentials  molecular  crystal  kinetics  reaction selectivity  effects of  reaction type structures of product temperature wavelength pressure response to external actions (homogeneous/heterogeneous, single-crystal  single-crystal)  cooperative effects

  9. The effect of intermolecular interactions on the properties of assemblies on the structures of assemblies supramolecular synthesis  crystal engineering  statistical analyses of databases  prediction of crystal structures physical properties chemical reactivity important for practice  intermolecular potentials  molecular  crystal  kinetics  reaction selectivity  effects of  reaction type structures of product temperature wavelength pressure response to external actions (homogeneous/heterogeneous, single-crystal  single-crystal)  cooperative effects

  10. The effect of intermolecular interactions on the properties of assemblies on the structures of assemblies supramolecular synthesis  crystal engineering  statistical analyses of databases  prediction of crystal structures physical properties chemical reactivity important for practice  intermolecular potentials  molecular  crystal  kinetics  reaction selectivity  effects of  reaction type structures of product temperature wavelength pressure response to external actions (homogeneous/heterogeneous, single-crystal  single-crystal)  cooperative effects

  11. The effect of intermolecular interactions on the properties of assemblies on the structures of assemblies supramolecular synthesis  crystal engineering  statistical analyses of databases  prediction of crystal structures physical properties chemical reactivity important for practice  intermolecular potentials  molecular  crystal  kinetics  reaction selectivity  effects of  reaction type structures of product temperature wavelength pressure response to external actions (homogeneous/heterogeneous, single-crystal  single-crystal)  cooperative effects

  12. Steric restrictions Interactions in the second coordination sphere Cooperative phenomena Passive reaction cavity Active reaction cavity Flexible reaction cavity Feed-back phenomena Effects of environment

  13. Two groups of problems: • Effect of the environment on the reaction rate and the very possibility of the reaction • Response of the environment to the reaction

  14.  IntroductionEffects of the environment Response of the environment Conclusions

  15. Variation of the environment • Various outersphere anions • Different polymorphs • Continuous distortion of the structure (variable pressure / elastic deformation)

  16. [Co(NH3)5NO2]Cl(NO3) [Co(NH3)5NO2]Cl2

  17. (a’) a 0 (a’) c [Co(NH3)5NO2]I2, C2/m [Co(NH3)5NO2]I2, Pnma

  18. Effects of the environment: • Changes in the mechanism • Different reaction products (or no reaction at all in particular environments) • Kinetics • Spatial propagation (homogeneous / heterogeneous) • Single crystal  single crystal / Fragmentation of crystals

  19. Effects of the environment: • Changes in the mechanism • Different reaction products (or no reaction at all in particular environments) • Kinetics • Spatial propagation (homogeneous / heterogeneous) • Single crystal  single crystal / Fragmentation of crystals

  20. Linkage isomerization in [Co(NH3)5NCS]Cl2 Solution: intramolecular; crystal: intermolecular

  21. Effects of the environment: • Changes in the mechanism • Different reaction products (or no reaction at all in particular environments) • Kinetics • Spatial propagation (homogeneous / heterogeneous) • Single crystal  single crystal / Fragmentation of crystals

  22. Linkage isomerization in [Co(NH3)5NO2]An (intramolecular) T [Co(NH3)5ONO]An [Co(NH3)5NO2]An <-> hn Solution: 75% red-ox decomposition + 25% linkage isomerization An = 2Cl-, 2Br-, 2I-, 2F-, Cl-(NO3)-, 2(NO3)-, (SO4)2-, etc.  100% linkage isomerization Crystals: An = (C2O4)2-  no photoisomerization, 100% red-ox decomposition An = (SiF6 )2-  photoisomerization not complete (40%), no red-ox decomposition

  23. Effects of the environment: • Changes in the mechanism • Different reaction products (or no reaction at all in particular environments) • Kinetics • Spatial propagation (homogeneous / heterogeneous) • Single crystal  single crystal / Fragmentation of crystals

  24. Different outersphere species

  25. I- 0.6 Br- 0.4 0.2 SCN- Cl- 0.0 0 50 100 150 200 t, h Racemization of (+)-[Co(en)3]X3

  26. Linkage isomerization in [Co(NH3)5ONO]An

  27. «Free space» around the nitro-ligand in [Co(NH3)5NO2]XY XY = 2Cl- XY = 2Br- XY = Cl-(NO3)- XY = (C2O4)2- XY = 2I- XY = (SiF6)2-

  28. Different polymorphs

  29. Isomerization in the different polymorphs 2 1 2 1 [Co(NH3)5ONO]Cl2 3 2 1 [Co(NH3)5ONO]Br2 [Co(NH3)5ONO]I2

  30. Continuous distortion of the same structure (hydrostatic pressure)

  31. Effect of hydrostatic pressure on the linkage isomerization k1 [Co(NH3)5ONO]Br2 [Co(NH3)5NO2]Br2  k2 DV > 0 (!) but V# < 0 Pressure accelerates the reaction (!)

  32. Effect of hydrostatic pressure on the linkage isomerization k1 [Co(NH3)5ONO]Br2 [Co(NH3)5NO2]Br2  k2 DV > 0 (!) but V# < 0 Pressure accelerates the reaction (!)

  33. Effects of the environment: • Changes in the mechanism • Different reaction products (or no reaction at all in particular environments) • Kinetics • Spatial propagation (homogeneous / heterogeneous) • Single crystal  single crystal / Fragmentation of crystals

  34. Effects of the environment: • Changes in the mechanism • Different reaction products (or no reaction at all in particular environments) • Kinetics • Spatial propagation (homogeneous / heterogeneous) • Single crystal  single crystal / Fragmentation of crystals

  35. Linkage isomerization in [Co(NH3)5NO2]Cl(NO3)

  36. Variation of the environment Continuous distortion of the same structure (elastic bending)

  37. scale mirror holder crystal load laser light

  38. Effect of elastic bending on the linkage isomerization hn [Co(NH3)5NO2]Cl(NO3) [Co(NH3)5ONO]Cl(NO3)  DV < 0 (!) but V# > 0 Quantum yield decreases (!) in the elastically compressed parts of the crystals

  39. Effect of elastic bending on the linkage isomerization hn [Co(NH3)5NO2]Cl(NO3) [Co(NH3)5ONO]Cl(NO3)  DV < 0 (!) but V# > 0 Quantum yield decreases (!) in the elastically compressed parts of the crystals

  40.  Introduction Effects of the environment  Response of the environment Conclusions

  41. Effects of the environment: • Changes in the mechanism • Different reaction products (or no reaction at all in particular environments) • Kinetics • Spatial propagation (homogeneous / heterogeneous) • Single crystal -> single crystal / Fragmentation of crystals

  42. Response of the environment:  Changes in the mechanism  Different reaction products (or no reaction at all in particular environments)  Kinetics  Spatial propagation (homogeneous / heterogeneous)  Single crystal  single crystal / Fragmentation of crystals

  43. Macroscopic level Bending Fragmentation Microscopic level Changes in the interatomic distances  Shifts in the vibrational spectra Response: Lattice strain

  44. Macroscopic level Bending Fragmentation Microscopic level Changes in the interatomic distances  Shifts in the vibrational spectra Response: Lattice strain

  45. Linear strain induced by [Co(NH3)5NO2]XY  [Co(NH3)5ONO]XY linkage isomerization

  46. Nitro - nitrito linkage photoisomerization Hydrostatic pressure

  47. Linear strain in directions of atom-atom contacts in the structure of [Co(NH3)5NO2]Cl(NO3) Nitro - nitrito linkage photoisomerization Hydrostatic pressure

  48. Effect of elastic bending on the linkage isomerization hn [Co(NH3)5NO2]Cl(NO3) [Co(NH3)5ONO]Cl(NO3)  DV < 0 (!) but V# > 0 Quantum yield decreases (!) in the elastically compressed parts of the crystals