C(sp²)-C(sp³) Suzuki-Miyaura Cross-Coupling Using gem-Bis(boronates)

Area of Science:

• Organic Chemistry
• Synthetic Chemistry
• Medicinal Chemistry

Background:

• Suzuki-Miyaura cross-coupling is a vital reaction in organic synthesis.
• 1,2-diaryl ethane motifs are present in numerous biologically active compounds.
• Monoboronates are commonly used, but limitations exist.

Purpose of the Study:

• To develop a novel strategy using gem-bis(boronates) as surrogates for monoboronates.
• To demonstrate the efficiency and broad applicability of gem-bis(boronates) in Suzuki-Miyaura couplings.
• To synthesize the antituberculosis natural product, cusparine, using this new methodology.

Main Methods:

• Utilized gem-bis(boronates) in Suzuki-Miyaura cross-coupling reactions.
• Investigated the reactivity and substrate scope of gem-bis(boronates).
• Performed a concise synthesis of cusparine.

Main Results:

• Gem-bis(boronates) proved to be stable and accessible reagents.
• The method demonstrated high efficiency with minimal side product formation (e.g., β-hydride elimination).
• A shortened, effective, and scalable route to cusparine was achieved.

Conclusions:

• Gem-bis(boronates) are valuable and versatile reagents for accessing 1,2-diaryl ethane structures.
• This methodology offers significant advantages over traditional monoboronate approaches.
• The developed strategy is practical for natural product synthesis and potentially scalable.