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THE ROLE OF CRYSTALLINE ENVIRONMENT IN THE INTRA MOLECULAR REACTIONS. Elena V. Boldyreva REC-008 MDEST Novosibirsk State University & Institute of Solid State Chemistry RAS boldyrev@nsu.ru. Introduction Effects of the environment Response of the environment Conclusions.
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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
Introduction Effects of the environment Response of the environment Conclusions
Introduction Effects of the environment Response of the environment Conclusions
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)
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)
Molecular / ionic-molecular crystals • Van der Waals interactions • Hydrogen bonds • Other specific interactions
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
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
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
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
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
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
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
IntroductionEffects of the environment Response of the environment Conclusions
Variation of the environment • Various outersphere anions • Different polymorphs • Continuous distortion of the structure (variable pressure / elastic deformation)
[Co(NH3)5NO2]Cl(NO3) [Co(NH3)5NO2]Cl2
(a’) a 0 (a’) c [Co(NH3)5NO2]I2, C2/m [Co(NH3)5NO2]I2, Pnma
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
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
Linkage isomerization in [Co(NH3)5NCS]Cl2 Solution: intramolecular; crystal: intermolecular
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
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
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
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
«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-
Isomerization in the different polymorphs 2 1 2 1 [Co(NH3)5ONO]Cl2 3 2 1 [Co(NH3)5ONO]Br2 [Co(NH3)5ONO]I2
Continuous distortion of the same structure (hydrostatic pressure)
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 (!)
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 (!)
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
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
Variation of the environment Continuous distortion of the same structure (elastic bending)
scale mirror holder crystal load laser light
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
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
Introduction Effects of the environment Response of the environment Conclusions
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
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
Macroscopic level Bending Fragmentation Microscopic level Changes in the interatomic distances Shifts in the vibrational spectra Response: Lattice strain
Macroscopic level Bending Fragmentation Microscopic level Changes in the interatomic distances Shifts in the vibrational spectra Response: Lattice strain
Linear strain induced by [Co(NH3)5NO2]XY [Co(NH3)5ONO]XY linkage isomerization
Nitro - nitrito linkage photoisomerization Hydrostatic pressure
Linear strain in directions of atom-atom contacts in the structure of [Co(NH3)5NO2]Cl(NO3) Nitro - nitrito linkage photoisomerization Hydrostatic pressure
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