KetoneCatalyzed Asymmetric Epoxidation Reactions

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Ketone-Catalyzed Asymmetric Epoxidation Reactions
Rawal Group Meeting (Literature)
April 4, 2005
Ray Bishop
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Application of Asymmetric Epoxidation in Natural
Product Syntheses
MacDonald, F. et al Org. Lett 2000, 2, 2917.
Yang, D. et al J.Org. Chem. 2000, 65, 2208-2217.
Danishefsky, S. et al J. Org.Chem. 2001, 66,
4369-4378.
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Conditions for Converting Ketones into
Dioxiranes

H2O2 may also employed as a primary oxidant
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Inductive Effects on Dioxirane Reactivity
Yang, D. et al J.Org. Chem. 2000, 65, 2208-2217.
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First Generation Chiral Ketone Catalyst Design
olefins investigated
Curcis Chiral Ketones ees were less that 20
Curci, R. et al Chem. Commun 1984, 156-156.
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First Generation C2 Chiral Ketone Catalyst Design
trans-stilbene was the alkene substrate
Yang, D. et al J.Org. Chem. 2000, 65, 2208-2217.
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Stereoelectronic Effect on C2 Symmetric Catalyst
Activity
Yang, D. et al J.Org. Chem. 2000, 65, 2208-2217.
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Stereoelectronic Effect on C2 Symmetric Catalyst
Activity
Behar, V. et al Tetrahedron Lett. 2002, 43,
1943-1946.
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Stereoelectronic Effect on C2 Symmetric Catalyst
Activity
Tomioka, K. et al Tetrahedron Lett. 2002, 43,
631-633.
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Stereoelectronic Effect on C2 Symmetric Catalyst
Activity
ND not determined
Denmark, K. et al J. Org. Chem. 2002, 67,
3479-3486.
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Chiral Ketones Derived from Sugars
Mechanistic Hypothesis
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Epoxidation of Trisubstituted and
trans-Substituted Alkenes
ees determined and compared to conversion
Shi, Y et al J. Am. Chem. Soc. 2002, 43, 631-633.
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Use of H2O2 as a Primary Oxidant
Mechanistic Hypothesis
Shi, Y et al Tetrahedron 2001, 57, 5213-5218.
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Evaluation of Asymmetric Epoxidation with H2O2 as
a Primary Oxidant
ees determined and compared to conversion
Shi, Y et al Tetrahedron 2001, 57, 5213-5218.
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Mechanistic Hypotheses for Epoxidation
Stereoselectivity
Shi, Y et al Tetrahedron 2001, 57, 5213-5218.
Singleton D. et al J. Am. Chem.Soc 2001,127, ASAP.
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Inductive Effect on the Reactivity of the Chiral
Ketone Catalyst
Shi, Y et al Tetrahedron 2001, 57, 5213-5218.
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Inductive Effect on the Reactivity of the Chiral
Ketone Catalyst
results obtained with catalyst 3
Shi, Y et al J. Am. Chem. Soc. 2002, 124,
8792-8793.
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Design of a Catalyst which is More Suitable for
cis Olefins
rationale for incompatibility with cis alkenes
and terminal alkenes
Shi, Y et al J. Org. Chem. 2002, 67, 2435-2446.
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Synthesis of Modified Catalyst
Shi, Y et al J. Org. Chem. 2003, 68, 4963-4965.
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Typical Enantiomeric Excess Values Obtained from
the Modified Catalyst
Shi, Y et al J. Am. Chem. Soc. 2002, 67,
2435-2446.
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Kinetic Resoluion of With Asymmetric Epoxidation
Shi, Y et al J. Am. Chem. Soc. 2005, ASAP.
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Rationale for Kinetic Resolution of epoxides
Shi, Y et al J. Am. Chem. Soc. 2005, ASAP.
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Chiral Ketones Derived from D-Glucose
Shing et al Tetrahedron 2002, 58, 7545-7552.
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Evaluation of a Chiral Ketone Derived from Glucose
Shing et al Tetrahedron 2002, 58, 7545-7552.
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Evaluation of a Chiral Ketone Derived from Glucose
Shing et al Tetrahedron 2002, 58, 7545-7552.
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Chiral Ketones Derived From L-Arabinose
Shing et al Tetrahedron 2003, 59, 2159-2168.
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Evaluation of a Chiral Ketone Derived From
L-Arabinose
The Effect of pH on Catalyst Activity
Shing et al Tetrahedron 2003, 59, 2159-2168.
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Chiral Ketones Derived from D-(-)-Quinic Acid
Shi, Y. et al 1997, 62, 8622-8623.
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Chiral Ketones Derived from D-(-)-Quinic Acid
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Shi, Y. et al 1997, 62, 8622-8623.
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Chiral Ketones Derived from D-(-)-Quinic Acid
Shing et al Tetrahedron 2003, 59, 2159-2168.
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Evaluation of Chiral Ketones Derived from
D-(-)-Quinic Acid
Shing et al Tetrahedron 2003, 59, 2159-2168.
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Asymmetric Epoxidation with Chiral Cyclohexanones
Roberts, S. M. J. Synth. Org. Chem. Jpn. 2002,60,
342-349.
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