Deoxygenative Single-Carbon Atom Transfer: Accessing Strained Carbocycles From Alkenes and Aldehydes With Designer...

Area of Science:

• Organic Chemistry
• Synthetic Chemistry
• Catalysis

Background:

• Single-carbon atom transfer reactions are valuable for building molecular complexity.
• Existing methods often rely on carbene reactivity, limiting substrate scope.

Purpose of the Study:

• To develop a novel deoxygenative single-carbon atom transfer strategy.
• To enable the direct coupling of alkenes and aldehydes for synthesizing substituted alkylidenecyclopropanes.

Main Methods:

• Utilized a novel iodomethylphosphonium reagent.
• Employed photocatalytic atom-transfer radical addition and cyclizative Wittig olefination.
• Investigated reaction mechanisms through mechanistic studies.

Main Results:

• Successfully coupled alkenes and aldehydes to form substituted alkylidenecyclopropanes.
• The phosphonium reagent facilitated both radical addition and Wittig olefination.
• Achieved the formation of four new covalent bonds in a single transformation.

Conclusions:

• Developed an operationally simple and modular method for accessing highly strained small carbocycles.
• The strategy offers a new entry point from abundant starting materials.
• The electronically tailored phosphonium reagent is key to the method's success.