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Ketone-Catalyzed Asymmetric Epoxidation Reactions. 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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Application of Asymmetric Epoxidation in Natural Product Syntheses MacDonald, F. et al Org. Lett2000, 2, 2917. Yang, D. et al J.Org. Chem.2000, 65, 2208-2217. Danishefsky, S. et al J. Org.Chem.2001, 66, 4369-4378.
Conditions for Converting Ketones into Dioxiranes • H2O2 may also employed as a primary oxidant
Inductive Effects on Dioxirane Reactivity Yang, D. et al J.Org. Chem.2000, 65, 2208-2217.
First Generation Chiral Ketone Catalyst Design Curci’s Chiral Ketones: ee’s were less that 20% olefins investigated Curci, R. et al Chem. Commun1984, 156-156. 4
First Generation C2 Chiral Ketone Catalyst Design trans-stilbene was the alkene substrate 5 Yang, D. et al J.Org. Chem.2000, 65, 2208-2217.
Stereoelectronic Effect on C2 Symmetric Catalyst Activity Yang, D. et al J.Org. Chem.2000, 65, 2208-2217.
Stereoelectronic Effect on C2 Symmetric Catalyst Activity Behar, V. et al Tetrahedron Lett. 2002, 43, 1943-1946.
Stereoelectronic Effect on C2 Symmetric Catalyst Activity Tomioka, K. et al Tetrahedron Lett.2002, 43, 631-633.
Stereoelectronic Effect on C2 Symmetric Catalyst Activity 9 *ND = not determined Denmark, K. et al J. Org. Chem.2002, 67, 3479-3486.
Chiral Ketones Derived from Sugars Mechanistic Hypothesis 10
Epoxidation of Trisubstituted and trans-Substituted Alkenes ee’s determined and compared to % conversion Shi, Y et al J. Am. Chem. Soc. 2002, 43, 631-633.
Use of H2O2 as a Primary Oxidant Use of H2O2 as a Primary Oxidant Mechanistic Hypothesis Mechanistic Hypothesis Shi, Y et al Tetrahedron 2001, 57, 5213-5218. Shi, Y et al Tetrahedron 2001, 57, 5213-5218. 12 12
Evaluation of Asymmetric Epoxidation with H2O2 as a Primary Oxidant ee’s determined and compared to % conversion Shi, Y et al Tetrahedron 2001, 57, 5213-5218. 13
Mechanistic Hypotheses for Epoxidation Stereoselectivity Shi, Y et al Tetrahedron 2001, 57, 5213-5218. 14 Singleton D. et al J. Am. Chem.Soc 2001,127, ASAP.
Inductive Effect on the Reactivity of the Chiral Ketone Catalyst Shi, Y et al Tetrahedron 2001, 57, 5213-5218. 15
Inductive Effect on the Reactivity of the Chiral Ketone Catalyst * results obtained withcatalyst 3 Shi, Y et al J. Am. Chem. Soc. 2002, 124, 8792-8793.
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.
Synthesis of Modified Catalyst Synthesis of Modified Catalyst Shi, Y et al J. Org. Chem. 2003, 68, 4963-4965.
Typical Enantiomeric Excess Values Obtained from the Modified Catalyst Shi, Y et al J. Am. Chem. Soc. 2002, 67, 2435-2446. 19
Kinetic Resoluion of With Asymmetric Epoxidation Shi, Y et al J. Am. Chem. Soc. 2005, ASAP. 20
Rationale for Kinetic Resolution of epoxides Shi, Y et al J. Am. Chem. Soc. 2005, ASAP
Chiral Ketones Derived from D-Glucose Shing et al Tetrahedron2002, 58, 7545-7552. 22
Evaluation of a Chiral Ketone Derived from Glucose Shing et al Tetrahedron 2002, 58, 7545-7552. 23
Evaluation of a Chiral Ketone Derived from Glucose Shing et al Tetrahedron 2002, 58, 7545-7552. 24
Chiral Ketones Derived From L-Arabinose Shing et al Tetrahedron 2003, 59, 2159-2168
Evaluation of a Chiral Ketone Derived From L-Arabinose The Effect of pH on Catalyst Activity Shing et al Tetrahedron 2003, 59, 2159-2168.
Chiral Ketones Derived from D-(-)-Quinic Acid Shi, Y. et al 1997, 62, 8622-8623. 27
Chiral Ketones Derived from D-(-)-Quinic Acid Shi, Y. et al 1997, 62, 8622-8623.
Chiral Ketones Derived from D-(-)-Quinic Acid Shing et al Tetrahedron 2003, 59, 2159-2168. 29
Evaluation of Chiral Ketones Derived from D-(-)-Quinic Acid Shing et al Tetrahedron 2003, 59, 2159-2168. 30
Asymmetric Epoxidation with Chiral Cyclohexanones Roberts, S. M. J. Synth. Org. Chem. Jpn.2002,60, 342-349. 31