Olefin Functionalization/Isomerization Enables Stereoselective Alkene Synthesis.

Area of Science:

• Organic Chemistry
• Catalysis
• Synthetic Methodology

Background:

• Stereoselective synthesis of tri- and tetrasubstituted trans alkenes remains a significant challenge in organic chemistry.
• Existing methods often lack direct access to 1-aryl(boryl)-1-methyl-functionalized alkenes from readily available alpha-olefin substrates.

Purpose of the Study:

• To develop a catalytic manifold for the site- and trans-selective synthesis of diverse 1-aryl(boryl)-1-methyl-functionalized tri- and tetrasubstituted trans alkenes.
• To provide a more efficient and versatile method compared to existing transformations.

Main Methods:

• Utilized catalytic amounts of a nonprecious N-heterocyclic carbene-Ni(I) complex.
• Employed a sterically bulky base to promote the union of monosubstituted olefins with various electrophilic reagents.

Main Results:

• Achieved high yields (up to 92%) and excellent regio- and stereoselectivity (>98%) in the synthesis of tri- and tetrasubstituted alkenes.
• Demonstrated the protocol's ability to form both carbon- and heteroatom-substituted C=C bonds.
• Successfully applied the method in the concise stereoselective synthesis of biologically active compounds.

Conclusions:

• The developed N-heterocyclic carbene-Ni(I) catalyzed protocol offers a powerful and direct approach for constructing complex alkene architectures.
• This method provides significant advantages over current transformations, enabling access to valuable intermediates for drug discovery and materials science.