Chemistry - A European Journal
10.1002/chem.202000368
COMMUNICATION
Figure 4. Optimized structure for the complex BCF:diethylsulfate (2:2).
O
O
5
S
-
-
-
-
-
<5%
<5%
(
no)
no)
Acknowledgements
Cl
Cl
This work was supported in part by the Agence National de la
Recherche through the LabEx “Chemistry of Complex Systems”
(ANR-10-LABX-0026 CSC; CSC-MCE-15). Financial support
from the International Center for Frontier Research in Chemistry
6
-
(
(
icFRC) is gratefully acknowledged.
[
a] A complex was considered stable if it preserves a rectangular-shape and
planar hydrogen bond network as obtained in tetramer self-assembly of BCF
with nitro compounds. [b] Difference between the OH-stretching frequency of
-1
BCF in the complex and alone (3692.52 cm ). [c] Reaction monitored by
GCMS relative to dodecane as internal standard.
Keywords: Brønsted acid catalysis • molecular modeling • nitro
compounds • H-bond aggregation • rational de novo design
Notably, this is the first time that an additive other than a nitro
compound has been shown to induce changes in the kinetic
order dependence and an accelerating effect in the azidation
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In summary, DFT modeling of 2:2 H-bonded aggregates of
nitro compounds and BCF yields O-H stretching frequencies that
are predictive of the experimentally observed rates in reactions
that use the corresponding nitro compound as promoter and can
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2
006, 106, 3210–3235.
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1
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[5]
a
molecular structure and pK of the Brønsted acid or the bulk
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4
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