Synthesis and characterization of di-, tri- and tetraboronic acids based on phenyl- and thienylsilane cores

• Synthetic procedures for oligoboronic acids based on phenyl- and thienylsilane cores.
• Structures verified using multinuclear NMR spectroscopy and elemental analysis.
• Complex supramolecular structures of two diboronic acids based on fluorinated dimethyldiphenylsilanes.

The synthesis of a series of di- tri- and tetraboronic acids based on respective phenyl- and thienylsilane cores is described. The optimal protocols involved lithiation of respective arylsilane precursors using either deprotonative lithiation or halogen/lithium exchange with n-BuLi followed by treatment of resultant intermediates with B(Oi-Pr)3 and subsequent hydrolysis, which afforded final products in good yields. X-ray crystal structures of selected diboronic derivatives were determined showing that hydrogen-bonding interactions of B(OH)2 groups are the main factor governing the supramolecular assembly.

The synthesis of a series of di- tri- and tetraboronic acids based on respective phenyl- and thienylsilane cores is described.Figure optionsDownload as PowerPoint slide