Title: Preparation of Allyl Sulfoxides by Palladium-Catalyzed Allylic Alkylation of Sulfenate Anions
1Preparation of Allyl Sulfoxides by
Palladium-Catalyzed Allylic Alkylation of
Sulfenate Anions
- Guillaume Maitro, Guillaume Prestat,
- David Madec, and Giovanni Poli
J. Org. Chem. 2006, 71, 7449-7454
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2Allyl Sulfoxides
- Allyl sulfoxides are versatile and valuable
building blocks in organic synthesis . -
-
- It is proved by their use in the preparation of
various functionalized compounds and natural
products. -
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3Palladium-Catalyzed Allylic Alkylation of Sulfur
Nucleophiles
4Generations of Carbon-Heteroatom Bonds by
Palladium Complex
5Synthesis of Allyl Sulfoxides
6Mechanism of The Synthesis of Sulfenate
7Methods of Generation of Sulfenate Anions
- Sulfur oxidation
- Addition-elimination reaction
- Ring-opening reaction
- Ring manipulation route
- Sigmatropic rearrangement
- Metal insertion reaction
- Retro-Michael reaction
8Generation of Sulfenate Anions by Sulfur Oxidation
- Sulfenate anions are of limited stability.
- A competitive oxidative pathway leading to
symmetrical disulfides may occur. - The oxidizing agents employed up to now, m-CPBA
and hydrogen peroxide, were not particularly well
suited to this task.
9Generation of Sulfenate Anions by Metal Insertion
Reaction
10Generation of Sulfenate Anions by Ring-Opening
Reaction
11Methods of Generation of Sulfenate Anions
- Sulfur oxidation
- Addition-elimination reaction
- Ring-opening reaction
- Ring manipulation route
- Sigmatropic rearrangement
- Metal insertion reaction
- Retro-Michael reaction
12Generation of Sulfenate Anions by retro-Michael
reaction
13The Catalytic Cycle for Transition
Metal-Catalyzed Allylic Alkylations
14Preparation of ß-Sulfinylesters
15Mechanism of The Preparation of The
ß-Sulfinylesters
16Mechanism of The Formation of Sulfenate Anions
17Optimization of Reaction Conditions
18Allylic Acetates
19Palladium-Catalyzed Allylic Alkylation of
Sulfenate Anions
20The Interconversion Equilibrium between The Two
Diastereomers
21Palladium-Catalyzed Allylic Alkylation of
Sulfenate Anions
22Palladium-Catalyzed Allylic Alkylation of
Sulfenate Anions
23Allylic Alkylations in Biphasic Conditions
24Conclusions
- We have reported the first palladium-catalyzed
allylation of sulfenate anions. - This new, smooth, and operationally very simple
method further extends the set of sulfur-based
nucleophiles that can be successfully allylated
under palladium catalysis. - The stereogenic nature of the sulfur atom in the
generated allyl sulfoxides, and the potential
sulfoxide-sulfenate rearrangement associated to
these compounds are expected to make of this
reaction a synthetically interesting
transformation.
25n-BuLi/(-)-sparteine