Yamaguchi, Shigehiro published the artcilePhotophysical Properties Changes Caused by Hypercoordination of Organosilicon Compounds: From Trianthrylfluorosilane to Trianthryldifluorosilicate, Recommanded Product: Difluorodiphenylsilane, the publication is Journal of the American Chemical Society (2000), 122(28), 6793-6794, database is CAplus.
Modification of Ï-electron systems by the main group elements represents a new direction toward the construction of organic materials with unusual electronic structures and with unique functions such as sensory materials. One of the potential way may be to take advantage of the hypercoordination abilities of the main-group elements. The authors present the first example of controlling the photophys. properties derived from the hypercoordination of group 14 elements. As a group 14 compound having extended Ï-conjugated substituents, tri(9-anthryl)fluorosilane (I) with its unique photophys. properties due to the through-space interaction was used. The addition of fluoride ion to I produced tri(9-anthryl)difluorosilicate (II). The use of KF/[2.2.2]cryptand as a fluoride source made possible to isolate the silicate cryptand (IIK+/cryptand) in 74% yield. Tetrahedral flat geometry crystal structure of I was changed due to hypercoordination to nearly ideal trigonal bipyramidal structure in IIK+/cryptand. The changes in the optical absorption and fluorescence spectra were studied by addition of n-Bu4NF as a fluoride source to I. Upon formation of silicate IIBu4+ fluorescence intensity increased with â?0 nm hypsochromic shifts of the maximum, its absorption band was shifted into â?0 nm shorter range relative to I. The observed changes should be mainly ascribed not to the intrinsic electronic perturbation by the hypercoordination but to the decrease in the degree of the through-space interaction between the anthryl groups by the structural change from tetrahedral of I to trigonal bipyramidal of II. The large spectral change of fluorescence spectra upon transition from from I to II allowed to estimate the binding constant of I toward fluoride as to be 2.8(±0.2) x 104 M-1 at 20° C in THF. Photophys. properties of series of similar triarylfluorosilanes and corresponding silicates were also studied.
Journal of the American Chemical Society published new progress about 312-40-3. 312-40-3 belongs to catalysis-chemistry, auxiliary class Organic Silicones, name is Difluorodiphenylsilane, and the molecular formula is C18H28N2O7, Recommanded Product: Difluorodiphenylsilane.
Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia