Substitution of the laser borane anti-B18H22 with pyridine: a structural and photophysical study of some unusually structured macropolyhedral boron hydrides
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F18%3A10374435" target="_blank" >RIV/00216208:11310/18:10374435 - isvavai.cz</a>
Result on the web
<a href="https://doi.org/10.1039/c7dt03823b" target="_blank" >https://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>
Alternative languages
Result language
angličtina
Original language name
Substitution of the laser borane anti-B18H22 with pyridine: a structural and photophysical study of some unusually structured macropolyhedral boron hydrides
Original language description
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.
Czech name
—
Czech description
—
Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
—
OECD FORD branch
10402 - Inorganic and nuclear chemistry
Result continuities
Project
—
Continuities
S - Specificky vyzkum na vysokych skolach<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2018
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Dalton Transactions
ISSN
1477-9226
e-ISSN
—
Volume of the periodical
47
Issue of the periodical within the volume
5
Country of publishing house
GB - UNITED KINGDOM
Number of pages
17
Pages from-to
1709-1725
UT code for WoS article
000423760500040
EID of the result in the Scopus database
2-s2.0-85041317988