Anion-Responsive Boron-Spiro-Centered π-Electronic Systems That Form Ion-Pairing Assemblies

Abstract

A variety of naphthalenediolates were orthogonally introduced to the boron unit of dipyrrolyldiketone boron complexes, exhibiting electronic properties that depended on the substituting positions of the naphthyl moieties. Combining the anion complexes with countercations resulted in the formation of ion-pairing assemblies with supporting stacking interactions of the naphthyl units.

“Homoleptic” Tetracoordinate Boron Compounds

“…Maeda et al reported that a series of naphthalenediols can be orthogonally introduced to the boron unit of dipyrrolyl diketone boron complexes, which were generated in situ from dipyrrolyl diketones and BCl 3 (Scheme S8). The unique spiroborate structure gives rise to two kinds of π electronic systems that are perpendicular to each other. These boron complexes exhibited effective anion-binding behavior in the solution state and also formed diverse stacking assemblies.…”

π-Electronic ion pairs: building blocks for supramolecular nanoarchitectonics viaiπ–iπ interactions

“…78 Furthermore, introducing naphthalenediolate units instead of two fluorine moieties at the boron unit affects the assembling modes. 79 In the assembly of the naphthalene-2,3-diolate boron complex as a 3 TATA + ion pair 3 TATA + - 43a ·Cl − , the stacked 3 TATA + dimer is sandwiched by the naphthyl unit of 43a ·Cl − . Conversely, in 3 TATA + - 43b ·Cl − , alternately stacked 3 TATA + and the receptor–Cl − complex unit in 43b ·Cl − are observed (Fig.…”