168
M. Heshmat et al.
Abbreviations
AIMD
Ab Initio Molecular Dynamics
BCF
Tris(pentafluorophenyl)borane
BDI
β-Diketiminato
Cy
Cyclohexyl
DABCO 1,4-diazabicyclo[2.2.2]octane
DFT
Density Functional Theory
Dipp
2,6-Diisopropylphenyl = C 6 H 3 iPr 2
EDA
Energy Decomposition Analysis
FES
Free Energy Surface
HOMO
Highest Occupied Molecular Orbital
FMO
Frontier Molecular Orbital
FLP
Frustrated Lewis Pair
EF model Electric Field model
ET model Electron Transfer model
LA
Lewis Acid
LB
Lewis Base
LUMO
Lowest Unoccupied Molecular Orbital
Me
Methyl
Mes
Mesityl (2,4,6-trimethylphenyl)
MD
Molecular Dynamics
MO
Molecular Orbital
MOF
Metal Organic Framework
NMR
Nuclear Magnetic Resonance
PES
Potential Energy Surface
Ph
Phenyl
THF
Tetrahydrofuran
TS
Transition State
VdW
Van der Waals
5.1 Introduction
Molecular hydrogen is an essential component in various chemical processes. For
example, (i) H 2 is the energy carrier in the foreseen sustainable hydrogen economy
concept, and (ii) in organic synthesis, H 2 is used as a reagent in many practically important reactions, such as hydrogenation of unsaturated carbon–carbon and
carbon–heteroatom bonds. In all these processes, the primary step is H 2 activation,
which is the stretching or breaking of the H–H bond. However, the H 2 covalent bond
is strong with very little polarizability. Thus, activation of H 2 remains a hard task.
While transition-metalbased H 2 activation catalysts remain indisputably important
[1], alternative main-group (metal-free) catalytic systems have been proposed and
M. Heshmat et al.
Abbreviations
AIMD
Ab Initio Molecular Dynamics
BCF
Tris(pentafluorophenyl)borane
BDI
β-Diketiminato
Cy
Cyclohexyl
DABCO 1,4-diazabicyclo[2.2.2]octane
DFT
Density Functional Theory
Dipp
2,6-Diisopropylphenyl = C 6 H 3 iPr 2
EDA
Energy Decomposition Analysis
FES
Free Energy Surface
HOMO
Highest Occupied Molecular Orbital
FMO
Frontier Molecular Orbital
FLP
Frustrated Lewis Pair
EF model Electric Field model
ET model Electron Transfer model
LA
Lewis Acid
LB
Lewis Base
LUMO
Lowest Unoccupied Molecular Orbital
Me
Methyl
Mes
Mesityl (2,4,6-trimethylphenyl)
MD
Molecular Dynamics
MO
Molecular Orbital
MOF
Metal Organic Framework
NMR
Nuclear Magnetic Resonance
PES
Potential Energy Surface
Ph
Phenyl
THF
Tetrahydrofuran
TS
Transition State
VdW
Van der Waals
5.1 Introduction
Molecular hydrogen is an essential component in various chemical processes. For
example, (i) H 2 is the energy carrier in the foreseen sustainable hydrogen economy
concept, and (ii) in organic synthesis, H 2 is used as a reagent in many practically important reactions, such as hydrogenation of unsaturated carbon–carbon and
carbon–heteroatom bonds. In all these processes, the primary step is H 2 activation,
which is the stretching or breaking of the H–H bond. However, the H 2 covalent bond
is strong with very little polarizability. Thus, activation of H 2 remains a hard task.
While transition-metalbased H 2 activation catalysts remain indisputably important
[1], alternative main-group (metal-free) catalytic systems have been proposed and