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

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

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

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

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

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

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

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

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

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

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

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

 Introduction  Effects 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(NH 3 ) 5 NO 2 ]Cl 2 [Co(NH 3 ) 5 NO 2 ]Cl(NO 3 )

a (a’)c0 [Co(NH 3 ) 5 NO 2 ]I 2, Pnma [Co(NH 3 ) 5 NO 2 ]I 2, C2/m

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(NH 3 ) 5 NCS]Cl 2 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

[Co(NH 3 ) 5 ONO]An[Co(NH 3 ) 5 NO 2 ]An An = 2Cl -, 2Br -, 2I -, 2F -, Cl - (NO 3 ) -, 2(NO 3 ) -, (SO 4 ) 2-, etc.  100% linkage isomerization h T Linkage isomerization in [Co(NH 3 ) 5 NO 2 ]An (intramolecular) Solution: Crystals: An = (C 2 O 4 ) 2-  no photoisomerization, 100% red-ox decomposition An = (SiF 6 ) 2-  photoisomerization not complete (40%), no red-ox decomposition 75% red-ox decomposition + 25% linkage isomerization

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

Different outersphere species

Racemization of (+)-[Co(en) 3 ]X t, h  Cl - SCN - Br - I-I-

Linkage isomerization in [Co(NH 3 ) 5 ONO]An

«Free space» around the nitro-ligand in [Co(NH 3 ) 5 NO 2 ]XY XY = 2Cl - XY = 2Br - XY = Cl - (NO 3 ) - XY = 2I - XY = (SiF 6 ) 2- XY = (C 2 O 4 ) 2-

Different polymorphs

[Co(NH 3 ) 5 ONO]Cl 2 [Co(NH 3 ) 5 ONO]Br 2 [Co(NH 3 ) 5 ONO]I 2 Isomerization in the different polymorphs

Continuous distortion of the same structure (hydrostatic pressure)

Effect of hydrostatic pressure on the linkage isomerization [Co(NH 3 ) 5 ONO]Br 2 [Co(NH 3 ) 5 NO 2 ]Br 2  k1k1 k2k2  V > 0 (!) but V # < 0 Pressure accelerates the reaction (!)

Effect of hydrostatic pressure on the linkage isomerization [Co(NH 3 ) 5 ONO]Br 2 [Co(NH 3 ) 5 NO 2 ]Br 2  k1k1 k2k2  V > 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

Linkage isomerization in [Co(NH 3 ) 5 NO 2 ]Cl(NO 3 )

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

holder crystal mirror load laser scale light

Effect of elastic bending on the linkage isomerization [Co(NH 3 ) 5 NO 2 ]Cl(NO 3 ) [Co(NH 3 ) 5 ONO]Cl(NO 3 )   V < 0 (!) but V # > 0 Quantum yield decreases (!) in the elastically compressed parts of the crystals h

Effect of elastic bending on the linkage isomerization [Co(NH 3 ) 5 NO 2 ]Cl(NO 3 ) [Co(NH 3 ) 5 ONO]Cl(NO 3 )   V < 0 (!) but V # > 0 Quantum yield decreases (!) in the elastically compressed parts of the crystals h

 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

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

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

Linear strain induced by [Co(NH 3 ) 5 NO 2 ]XY  [Co(NH 3 ) 5 ONO]XY linkage isomerization

Hydrostatic pressure Nitro - nitrito linkage photoisomerization

Linear strain in directions of atom-atom contacts in the structure of [Co(NH 3 ) 5 NO 2 ]Cl(NO 3 ) Nitro - nitrito linkage photoisomerization Hydrostatic pressure

Effect of elastic bending on the linkage isomerization [Co(NH 3 ) 5 NO 2 ]Cl(NO 3 ) [Co(NH 3 ) 5 ONO]Cl(NO 3 )   V < 0 (!) but V # > 0 Quantum yield decreases (!) in the elastically compressed parts of the crystals h

[Co(NH 3 ) 5 ONO]Br 2 Nitrito-nitro linkage thermal isomerization Hydrostatic pressure

Effect of hydrostatic pressure on the linkage isomerization [Co(NH 3 ) 5 ONO]Br 2 [Co(NH 3 ) 5 NO 2 ]Br 2  k1k1 k2k2  V > 0 (!) but V # < 0 Pressure accelerates the reaction (!)

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

“Реакция неотделима от среды, в которой она протекает” Н. Меншуткин, 1890 г.

“A reaction cannot be separated from the medium” N. Menschutkin, 1890 г.

Medium = Environment Solvent Cages of various types Crystalline environment in molecular crystals