Substitution of the laser borane anti-B18H22 with pyridine: a structural and photophysical study of some unusually structured acropolyhedral boron hydrides

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388980%3A_____%2F18%3A00486863" target="_blank" >RIV/61388980:_____/18:00486863 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1039/c7dt03823b" target="_blank" >http://dx.doi.org/10.1039/c7dt03823b</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/c7dt03823b" target="_blank" >10.1039/c7dt03823b</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Substitution of the laser borane anti-B18H22 with pyridine: a structural and photophysical study of some unusually structured acropolyhedral boron hydrides

Popis výsledku v původním jazyce

Reaction of anti-B18H22 1 with pyridine in neutral solvents gives sparingly soluble B16H18-3', 8'-Py-2 3a as the major product (ca. 53%) and B18H20-6', 9'-Py-2 2 (ca. 15%) as the minor product, with small quantities of B18H20-8'-Py 4 (ca. 1%) also being formed. The three new compounds 2, 3a and 4 are characterized by single-crystal X-ray diffraction analyses and by multinuclear multiple-resonance NMR spectroscopy. Compound 2 is of ten-vertex nido: ten-vertex arachno two-atoms-in-common architecture, long postulated for a species with borons-only cluster constitution, but previously elusive. Compound 3a is of unprecedented ten-vertex nido: eight-vertex arachno two-atoms-in-common architecture. The singlecrystal X-ray diffraction analysis for the picoline derivative B16H18(NC5H4Me)(2) 3b, similarly obtained, is also presented. B18H20Py 4 is also previously unreported but is of known ten-vertex nido: ten-vertex nido twoatoms- in-common architecture of anti configuration, but now with the pyridine ligand positioned differently to other reported examples of B18H20L compounds. Factors behind the remarkably low solubility of 3a and 3b are elucidated in terms of electrostatic potential (ESP) calculations, polarity, and van der Waals complementarities. In view of contemporary developing high interest in the fluorescent properties of macropolyhedral boron-containing species, a detailed assessment of the photophysical characteristics of 3a and 4 is also presented. In contrast to the thermochromic fluorescence of 2 (from 620 nm brick-red at room temperature to 585 nm yellow at 8 K, quantum yield 0.15), compound 3a is only weakly phosphorescent in the yellow region (590 nm, quantum yield 0.01), whereas compound 4 exhibits no luminescence. The far more photoactive nature of compound 2 is associated with S-1 excited-state minima structures that differ from each other only by the relative rotational positions of the pyridine substituents on its disubstituted ten-vertex {arachno-B10Py2}-subcluster. The wavelength and relative intensity of fluorescence from these structures depends on the rotational positions of the pyridine ligands, which in turn are influenced by temperature and/or rotational inhibition in the solid-state.

Název v anglickém jazyce

Substitution of the laser borane anti-B18H22 with pyridine: a structural and photophysical study of some unusually structured acropolyhedral boron hydrides

Popis výsledku anglicky

Reaction of anti-B18H22 1 with pyridine in neutral solvents gives sparingly soluble B16H18-3', 8'-Py-2 3a as the major product (ca. 53%) and B18H20-6', 9'-Py-2 2 (ca. 15%) as the minor product, with small quantities of B18H20-8'-Py 4 (ca. 1%) also being formed. The three new compounds 2, 3a and 4 are characterized by single-crystal X-ray diffraction analyses and by multinuclear multiple-resonance NMR spectroscopy. Compound 2 is of ten-vertex nido: ten-vertex arachno two-atoms-in-common architecture, long postulated for a species with borons-only cluster constitution, but previously elusive. Compound 3a is of unprecedented ten-vertex nido: eight-vertex arachno two-atoms-in-common architecture. The singlecrystal X-ray diffraction analysis for the picoline derivative B16H18(NC5H4Me)(2) 3b, similarly obtained, is also presented. B18H20Py 4 is also previously unreported but is of known ten-vertex nido: ten-vertex nido twoatoms- in-common architecture of anti configuration, but now with the pyridine ligand positioned differently to other reported examples of B18H20L compounds. Factors behind the remarkably low solubility of 3a and 3b are elucidated in terms of electrostatic potential (ESP) calculations, polarity, and van der Waals complementarities. In view of contemporary developing high interest in the fluorescent properties of macropolyhedral boron-containing species, a detailed assessment of the photophysical characteristics of 3a and 4 is also presented. In contrast to the thermochromic fluorescence of 2 (from 620 nm brick-red at room temperature to 585 nm yellow at 8 K, quantum yield 0.15), compound 3a is only weakly phosphorescent in the yellow region (590 nm, quantum yield 0.01), whereas compound 4 exhibits no luminescence. The far more photoactive nature of compound 2 is associated with S-1 excited-state minima structures that differ from each other only by the relative rotational positions of the pyridine substituents on its disubstituted ten-vertex {arachno-B10Py2}-subcluster. The wavelength and relative intensity of fluorescence from these structures depends on the rotational positions of the pyridine ligands, which in turn are influenced by temperature and/or rotational inhibition in the solid-state.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10402 - Inorganic and nuclear chemistry

Projekt

<a href="/cs/project/GA18-20286S" target="_blank" >GA18-20286S: Klastry hydridů boru pro lasery: Pochopení chemických a strukturálních faktorů, které určují fotofyziku anti-B18H22 a jejích derivátů</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Dalton Transactions

ISSN

1477-9226

e-ISSN

—

Svazek periodika

47

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

17

Strana od-do

1709-1725

Kód UT WoS článku

000423760500040

EID výsledku v databázi Scopus

2-s2.0-85041317988