The Effect of Branching on the One‐ and Two‐Photon Absorption, Cell Viability, and Localization of Cationic Triarylborane Chromophores with Dipolar versus Octupolar Charge Distributions for Cellular Imaging

Abstract

Twod ifferentchromophores,n amely ad ipolar and an octupolar system,w ere prepared and their linear and nonlinear optical properties as well as their bioimaging capabilities were compared. Both contain triphenylamine as the donor and at riarylboranea st he acceptor, the latter modified with cationic trimethylammonio groups to provide solubility in aqueous media. The octupolar systeme xhibits a much higher two-photon brightness, and also better cell viability and enhanced selectivity for lysosomes comparedw ith the dipolar chromophore. Furthermore, both dyes were applied in two-photon excitedf luorescence( TPEF) live-cell imaging.[**] We are aware that the dipole moment m in our charged compounds is origin-dependenta nd not an observable quantity. [35] For simplification, we use the term dipole moment to describe the electron-density distribution in our chargedc ompounds. Thus,the terms dipole and octupole are used accordingly.Supporting information and the ORCID identification number(s) for the author(s) of this articlecan be found under: https://doi.org/10.

Highly Stable, Readily Reducible, Fluorescent, Trifluoromethylated 9‐Borafluorenes

“…Thus, three‐coordinate boranes can be employed as π‐acceptors, single‐electron or electron‐pair acceptors. Such boranes have been used in linear and non‐linear optical materials, anion sensors, frustrated Lewis pairs (FLPs), as well as in organic light‐emitting diodes (OLEDs) . There are numerous examples, both aromatic and antiaromatic, of boron‐containing conjugated cyclic π‐systems .…”

Insights into the Optical Properties of Triarylboranes with Strongly Electron‐Accepting Bis(fluoromesityl)boryl Groups: when Theory Meets Experiment

“…A large number of air-stable conjugated three-coordinate organoboron compounds have been synthesized over the last few decades [1][2][3][4][5][6][7][8] for various applications, particularly in linear [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] and nonlinear [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39] optics, electro-optic devices, [40][41][42] anion sensors, [43,44] cell imaging, [45][46][47][48] etc. The boron center in these species possesses an empty p-orbital and can thus serve as a strong π-acceptor following photo-excitation, or as a readily reducible center.…”

(Hetero)arene-fused boroles: a broad spectrum of applications

“…In 2014, Wagner and co-workers linked two 9-borauorenes by a biphenyl (18) and carried out the one electron reduction with lithium naphthalenide in toluene (Scheme 21), 150 obtaining [18]Li$(THF) 4 Â 0.5C 10 H 8 as black crystals. Single crystal Xray diffraction shows that the distance between the two boron centers of [18]Li$(THF) 4 Â 0.5C 10 H 8 is 2.265(4)Å, which is 0.655 A shorter than that in its precursor 18 (2.920(6)Å) ( Fig. 6), 84 can be prepared in quantitative yields and represents an extremely rare example of diborane(6) dianions).…”