Acyclic Remote 1,6-Stereoselection.
Karla Janardhan Reddy1, Tapan Kumar Kuilya1, Jin Kun Cha1
1Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States.
Organic Letters
|August 22, 2022
Summary
A new Ti-O linker strategy enables stereochemical control in reactions involving aldehydes. This method simplifies reagent preparation and reveals solvent effects on diastereoselectivity.
Area of Science:
- Organic Chemistry
- Stereochemistry
- Catalysis
Background:
- Stereochemical control is crucial in organic synthesis.
- Homopropargylation and homoallylation reactions are important carbon-carbon bond-forming reactions.
- Existing methods often require pre-functionalized reagents.
Purpose of the Study:
- To develop a novel strategy for stereoselective homopropargylation and homoallylation of aldehydes.
- To utilize readily available alcohol derivatives as pronucleophiles.
- To investigate factors influencing diastereoselectivity.
Main Methods:
- Employed a Titanium-Oxygen (Ti-O) temporary linker strategy.
- Used propargylic and allylic alcohol derivatives as pronucleophiles.
- Analyzed the influence of Grignard reagents and reaction solvents on stereochemical outcomes.
Main Results:
- Achieved stereochemical communication in homopropargylation and homoallylation of aldehydes.
- Demonstrated the utility of alcohol derivatives, avoiding complex reagent synthesis.
- Observed that 1,6-diastereoselectivity is sensitive to both the Grignard reagent and the solvent.
Conclusions:
- The Ti-O temporary linker strategy provides an efficient route to stereocontrolled homopropargylation and homoallylation.
- The use of alcohol derivatives simplifies synthetic procedures.
- Reaction solvent is a critical parameter influencing diastereoselectivity in these transformations.
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