Benzo‐ and Naphthoborepins: Blue‐Emitting Boron Analogues of Higher Acenes

Abstract

Feelin' Blue: Extended aromatic systems with a borepin core (see picture) can be synthesized by tin–boron exchange. The properties of these air‐ and moisture‐tolerant materials include strong blue fluorescence.

A Computational Study on a Strategy for Isolating a Stable Cyclopentadienyl Cation

“…This would also provide opportunities to increase the steric shielding on the cationic carbon for improved kinetic stability. For example, mesityl groups are able to render a three‐coordinate boron in a borepin ring system sufficiently unreactive with respect to water that it may be purified by column chromatography 27. Our data suggests that a derivative with Ph at the 1 position, CF 3 at the 2 and 5 and CH 3 at the 3 and 4 positions would be the optimal derivative ( 13 ) to stabilize [Cp] + .…”

Assessment of the aromaticity of borepin rings by spectroscopic, crystallographic and computational methods: a historical overview

“…However, the field of borepin research lay experimentally dormant for 16 years before Mercier et al . synthesized three benzo‐ and naptho‐fused [ b , f ]borepins as light‐emitting chromophores in 2009 ( 46 CCDC# 730729; 47 CCDC # 730730; 48 CCDC# 730731) and also found that B ‐Mes borepins were resistant to oxidation in solution and stable to chromatography . As shown in (Table ), the H γ peaks shift to lower frequency as the size of the acenes fused to the borepin increases.…”

A novel synthesis of stable 3H-pyrrolizine fused diazaborepin

“…[1][2][3][4][5][6] Heteropines incorporated heteroatoms such as B,7,8 Al, 9 Ga, 10,11 Si, 12,13 Ge, 14 Sn, 15 P, 16,17 As, 18 Bi, 18 and Se. 14 B-heteropine, denoted as borepin with a heterocyclic ring containing only boron and carbon atoms was used by Letsinger et al 19 in 1955.…”

“…Piers and co-workers synthesized aromatic fused B-mesityl borepin which was stable enough toward adventitious moisture and purified by column chromatography within several hours. 15 Tovar and co-workers reported para-and meta-B-entacene, respectively, containing two borepin rings with stable structure in air for months purified by silica gel chromatography. 5,7,8 In this contribution, we reported the design, organocatalysis synthesis, and characterization of the original example of seven member stable 3H-pyrrolizine fused diazaborepin via B-N chemistry.…”