Exploiting Boron Coordination: B←N Bond Supports a [2+2] Photodimerization in the Solid State and Generation of a Diboron Bis‐Tweezer for Benzene/Thiophene Separation

Abstract

Nc oordination supports a[ 2 + +2] photodimerization in the solid state.The bond is defined by an orthogonal interaction between stilbazole and ap henylboronic ester to enable astereocontrolled and rapid photoreaction. The cyclobutane photoproduct affords an ovel diboron bis-tweezer adduct that is used to separate am ixture of benzene and thiophene upon crystallization.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

Channel Confinement of Aromatic Petrochemicals via Aryl–Perfluoroaryl Interactions With a B←N Host

“…The stilbazole pf-sbz is coordinated to be through a B←N bond [1.674(3) Å] forming a discrete T-shaped adduct. The tetrahedral character of boron ( THC = 71.7%) (Höpfl, 1999) shows the strength of the B←N bond to be comparable to similar adducts (Cruz-Huerta et al, 2016; Campillo-Alvarado et al, 2019). The fluorinated alkene adopts a twisted conformation (29.3°), while the pyridyl ring lies approximately orthogonal (89.7°) to the best plane of atoms C1, O1, and O2.…”

“…The inclusion behavior of be-pf-sbz contrasts B←N adducts with bipyridines. The ditopic B←N adducts generate completely enclosed cavities vs. channels owing to the presence of edge-to-face π···π interactions with additional boronic esters (Campillo-Alvarado et al, 2018c, 2019). The generation of porous extended frameworks based on the B←N interactions has been recently explored (Cruz-Huerta et al, 2012; Stephens et al, 2019).…”

“…In this context, an emerging solid-state ordering strategy relies on the use of boronic acids and derivatives to confine guests into a crystal lattice (Nishiyabu et al, 2011; Bull et al, 2013). The inclusion properties are facilitated by multiple supramolecular interactions of boronic acids and derivatives (e.g., hydrogen bonding (Campillo-Alvarado et al, 2018a,b; Ruelas-Alvarez et al, 2019), reversible esterification Fornasari et al, 2019; Takahashi et al, 2019, π-π interactions and B←N coordination Campillo-Alvarado et al, 2019; Ono and Hisaeda, 2019; Stephens et al, 2019).…”

Boron–Nitrogen Double Tweezers Comprising Arylboronic Esters and Diamines: Self‐Assembly in Solution and Adaptability as Hosts for Aromatic Guests in the Solid State

“…Interestingly, guest recognition may occur in both cavities within this framework resembling a double‐tweezer host, and structural syn / anti ‐isomerism is feasible, which might enable the encapsulation of even two different guest molecules (Scheme c). Moreover, these double‐tweezer hosts were shown to perform “catch‐release” cycles of polycyclic aromatic hydrocarbons (PAHs) such as pyrene from solution mixtures, to accomplish the separation of o ‐xylene from an equimolar mixture of o ‐, m ‐ and p ‐xylene isomers by enrichment through fractional crystallization, and to behave as molecular scavengers for the selective removal of sulfur‐based aromatics such as thiophene …”

Single-Crystal-to-Single-Crystal [2 + 2] Photodimerization Involving B←N Coordination with Generation of a Thiophene Host

“…Recently, B←N coordination has been reported to support a [2 + 2] photocycloaddition in the solid state to form a molecular bis-tweezer . The resulting B-based tweezer was used to separate thiophene from benzene, a vital separation in petrochemistry .…”