Selectivity of Encapsulated Aldehyde CH Activation Reactions

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Selectivity of Encapsulated Aldehyde C-H
Activation Reactions
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75C
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Not encapsulated
D. Leung, K. N. Raymond, R. G. Bergman, 2003-4
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A Nanovessel-Catalyzed Unimolecular Reaction
Initial rates for different catalyst loadings
k27cat. 1.17 x 10-4 s-1 k40cat. 1.80 x
10-4 s-1 kuncat. lt 10-6 s-1 D. Fiedler, K. N.
Raymond, R. G. Bergman, 2004
3
Suggestions of Topics for Discussion at
Selectivity Control Session

• Redox-coupled or -switchable catalysts
• Use of redox centers to tune catalytic properties
• The next generation of ligand design (e.g.,
  ligands that recognize specific substrates or
  sense their environment, megaligands, new
  facial ligand classes
• Ways to develop new supramolecular and
  nanovessel catalysts--how to move from binding
  studies to the development of useful materials
  understanding the principles that control
  catalysis in active sites of enzymes and large
  synthetic molecular systems
• Use of molecular switches and other nanoscale
  devices to control catalysts and turn them on and
  off how to combine developing sensor technology
  with catalyst technology
• Design of multidentate ligands to allow
  well-defined surface coordination and catalysis
• Biocatalysts how to understand and use them
• Ways to develop new biocatalysts or hybrid
  synthetic/biocatalysts (e.g., catalytic
  antibodies, ligands derived from proteins,
  biotin, sugars, etc., enzymes from exotic
  environments, rapid evolution methods, synthetic
  modification of natural biocatalysts, use of
  genetic methods to modify known biocatalysts,
  design of biomimetic O2-evolving systems, etc.)
• Biomimetic catalysis - what can we learn from
  nature about designing synthetic catalysts that
  will do what nature can do, but we cannot (e.g.,
  C-H activation that mimics MMO or Cyt P450,
  methanogenesis)?
• Understanding and improving homogeneous
  enantioselective catalysis--especially nonlinear
  effects, asymmetric amplification in
  autocatalytic reactions,
• Understanding and improving enantioselective
  surface-catalyzed reactions surfaces modified
  with chiral molecules, inherently chiral surface
  structures, molecular imprinting of surfaces with
  chiral reagents
• Organo- and main group catalysis likelihood--and
  advantages and disadvantages--of replacing
  enantioselective metal catalysts with organic
  catalysts or main group catalysts
• Catalysts or compatible combinations of catalysts
  capable of carrying out tandem (sequential)
  transformations in one vessel possibility of
  designing tandem homogeneous/heterogeneous
  processes

Robert G. Bergman