Merging Borylation and Desaturation to Access Arylboronates from Carbonyls

Area of Science:

• Organic Synthesis
• Organoboron Chemistry
• Sustainable Chemistry

Background:

• Aryl boronates are crucial building blocks in organic synthesis, particularly for cross-coupling reactions.
• Existing methods for aryl boronate synthesis often involve harsh conditions, toxic reagents, or multiple steps.
• There is a need for efficient, selective, and environmentally benign methods for aryl boronate preparation.

Purpose of the Study:

• To develop a novel, efficient, and highly selective method for synthesizing aryl boronates from readily available carbonyl compounds.
• To explore the utility of this method for the late-stage functionalization of biorelevant molecules.
• To investigate the underlying reaction mechanism and the unique oxidative properties of the NaHMDS/diboron system.

Main Methods:

• Utilized sodium bis(trimethylsilyl)amide (NaHMDS) as a promoter for the borylation reaction.
• Employed carbonyl compounds as starting materials for the synthesis of aryl boronates.
• Investigated the reaction pathway through experimental studies, focusing on C-O bond borylation and desaturation.

Main Results:

• Achieved efficient and highly selective synthesis of aryl boronates from carbonyl compounds.
• Demonstrated the environmental sustainability of the method, with no halogenated waste and no requirement for catalysts or additives.
• Successfully applied the protocol for the late-stage borylation of biorelevant compounds, yielding diverse naphthalene derivatives.
• Identified unprecedented oxidative properties of the NaHMDS/diboron reagent system.

Conclusions:

• The NaHMDS-promoted method provides a versatile and sustainable platform for aryl boronate synthesis from carbonyl compounds.
• This approach facilitates late-stage borylation, expanding synthetic possibilities for complex molecules.
• The discovered oxidative properties of the NaHMDS/diboron system open new avenues in synthetic methodology development.