Acylboranes: synthetic strategies and applications

Area of Science:

• Organic Chemistry
• Organoboron Chemistry

Background:

• Acylboranes are a rare class of boron compounds.
• They have been proposed as intermediates in various chemical transformations.
• Their preparation has historically been challenging.

Purpose of the Study:

• To provide an overview of acylborane synthesis and chemistry.
• To discuss recent advancements in acylborane preparation methodologies.
• To highlight the applications of acylboranes in organic synthesis.

Main Methods:

• Synthesis utilizing electrophilic boron reagents and acyl-anion equivalents.
• Preparation via nucleophilic boryl anion reagents reacting with electrophiles (aldehydes, carbonates, esters).
• New methods involving oxidation of MIDA α-hydroxyboronates or α-bromomethyl alcohol.
• A one-step catalytic C-B coupling reaction for acylborane synthesis from acyl chlorides and borylzinc reagents.

Main Results:

• Established methodologies for acylborane synthesis using diverse boron sources.
• Development of new synthetic routes, including oxidation and catalytic coupling reactions.
• Demonstrated utility of acylboranes in chemoselective amide-bond formation.
• Conversion of acylboranes into various functionalized boron derivatives.

Conclusions:

• Acylborane synthesis is now more accessible through various established and novel methods.
• Acylboranes serve as valuable intermediates for creating functionalized boron compounds.
• Their application in chemoselective amide-bond forming reactions is a significant advancement.