9 research outputs found
Two Types of Two-Component Gels Formed from Pseudoenantiomeric Ethynylhelicene Oligomers
Two-component gels formed from pseudoenantiomeric ethynylhelicene
oligomers in toluene exhibited two different properties depending
on difference in numbers of helicenes in the two components. The combinations
(<i>M</i>)-<b>5/</b>(<i>P</i>)-<b>4</b>, (<i>M</i>)-<b>6/</b>(<i>P</i>)-<b>4</b>, and (<i>M</i>)-<b>7/</b>(<i>P</i>)-<b>4</b>, which contained oligomers with comparable numbers
of helicenes, formed transparent gels (Type I gels). The combinations
(<i>M</i>)-<b>6/</b>(<i>P</i>)-<b>3</b>, (<i>M</i>)-<b>7/</b>(<i>P</i>)-<b>3</b>, and (<i>M</i>)-<b>8/</b>(<i>P</i>)-<b>3</b>, which contained oligomers with considerably different
numbers of helicenes, formed turbid gels (Type II gels). Negative
Cotton effects were observed for the Type I gels in the region between
350 and 450 nm, and were positive for the Type II gels, despite the
use of (<i>M</i>)-oligomers for the longer components. UV/vis
exhibited absorption maxima at 350 nm for the Type I gels and at 338
nm for the Type II gels. Different behaviors in gel formation processes
were observed by fluorescence studies. Atomic force microscopy analysis
showed fiber structures of 25–50 nm diameter for Type I gels
and bundles of 100–150 nm diameter for Type II gels. The stoichiometry
in gel formation also differed: The Type I gels showed 1:1 stoichiometry
of the two components; the Type II gels showed no 1:1 stoichiometry,
likely 1:2 stoichiometry. Using the Type I and II gels, two-layer
gel systems were constructed
Equatorenes: Synthesis and Properties of Chiral Naphthalene, Phenanthrene, Chrysene, and Pyrene Possessing Bis(1-adamantyl) Groups at the Peri-position
Chiral polycyclic aromatic hydrocarbons
containing bisÂ(1-adamantyl)
groups at the peri-positions, named equatorenes, were synthesized
in optically pure form starting from optically pure 4,5-bisÂ(1-adamantyl)-8-methoxy-1-naphthol.
A sequential Diels–Alder reaction of furan and arynes generated
from 1,2-bromotriflates provided tricyclic and tetracyclic epoxides,
and acid-catalyzed aromatization gave phenanthrol and chrysenol. Deoxygenation
reactions involving the hydrogenolysis of triflates gave 1,8-bisÂ(1-adamantyl)Ânaphthalene,
1,10-bisÂ(1-adamantyl)Âphenanthrene, and 1,12-bisÂ(1-adamantyl)Âchrysene.
3,4-BisÂ(1-adamantyl)Âpyrene was synthesized from phenanthrol by Sonogashira
coupling and Pt-catalyzed cyclization. Essentially no racemization
occurred during the synthesis. X-ray analysis indicated the distorted
naphthalene moiety possessing the peri-diadamantyl groups and the
flat structure of the other benzene rings. UV–vis analysis
of the equatorenes showed considerable redshifts compared with that
of the corresponding achiral arenes. Electrochemical analysis of the
naphthalene and pyrene indicated that the distortion decreased the
highest occupied molecular orbital stability with no marked effect
on the lowest unoccupied molecular orbital energy level, and the origin
was discussed on the basis of calculation results
Equatorenes: Synthesis and Properties of Chiral Naphthalene, Phenanthrene, Chrysene, and Pyrene Possessing Bis(1-adamantyl) Groups at the Peri-position
Chiral polycyclic aromatic hydrocarbons
containing bisÂ(1-adamantyl)
groups at the peri-positions, named equatorenes, were synthesized
in optically pure form starting from optically pure 4,5-bisÂ(1-adamantyl)-8-methoxy-1-naphthol.
A sequential Diels–Alder reaction of furan and arynes generated
from 1,2-bromotriflates provided tricyclic and tetracyclic epoxides,
and acid-catalyzed aromatization gave phenanthrol and chrysenol. Deoxygenation
reactions involving the hydrogenolysis of triflates gave 1,8-bisÂ(1-adamantyl)Ânaphthalene,
1,10-bisÂ(1-adamantyl)Âphenanthrene, and 1,12-bisÂ(1-adamantyl)Âchrysene.
3,4-BisÂ(1-adamantyl)Âpyrene was synthesized from phenanthrol by Sonogashira
coupling and Pt-catalyzed cyclization. Essentially no racemization
occurred during the synthesis. X-ray analysis indicated the distorted
naphthalene moiety possessing the peri-diadamantyl groups and the
flat structure of the other benzene rings. UV–vis analysis
of the equatorenes showed considerable redshifts compared with that
of the corresponding achiral arenes. Electrochemical analysis of the
naphthalene and pyrene indicated that the distortion decreased the
highest occupied molecular orbital stability with no marked effect
on the lowest unoccupied molecular orbital energy level, and the origin
was discussed on the basis of calculation results
Equatorenes: Synthesis and Properties of Chiral Naphthalene, Phenanthrene, Chrysene, and Pyrene Possessing Bis(1-adamantyl) Groups at the Peri-position
Chiral polycyclic aromatic hydrocarbons
containing bisÂ(1-adamantyl)
groups at the peri-positions, named equatorenes, were synthesized
in optically pure form starting from optically pure 4,5-bisÂ(1-adamantyl)-8-methoxy-1-naphthol.
A sequential Diels–Alder reaction of furan and arynes generated
from 1,2-bromotriflates provided tricyclic and tetracyclic epoxides,
and acid-catalyzed aromatization gave phenanthrol and chrysenol. Deoxygenation
reactions involving the hydrogenolysis of triflates gave 1,8-bisÂ(1-adamantyl)Ânaphthalene,
1,10-bisÂ(1-adamantyl)Âphenanthrene, and 1,12-bisÂ(1-adamantyl)Âchrysene.
3,4-BisÂ(1-adamantyl)Âpyrene was synthesized from phenanthrol by Sonogashira
coupling and Pt-catalyzed cyclization. Essentially no racemization
occurred during the synthesis. X-ray analysis indicated the distorted
naphthalene moiety possessing the peri-diadamantyl groups and the
flat structure of the other benzene rings. UV–vis analysis
of the equatorenes showed considerable redshifts compared with that
of the corresponding achiral arenes. Electrochemical analysis of the
naphthalene and pyrene indicated that the distortion decreased the
highest occupied molecular orbital stability with no marked effect
on the lowest unoccupied molecular orbital energy level, and the origin
was discussed on the basis of calculation results
Equatorenes: Synthesis and Properties of Chiral Naphthalene, Phenanthrene, Chrysene, and Pyrene Possessing Bis(1-adamantyl) Groups at the Peri-position
Chiral polycyclic aromatic hydrocarbons
containing bisÂ(1-adamantyl)
groups at the peri-positions, named equatorenes, were synthesized
in optically pure form starting from optically pure 4,5-bisÂ(1-adamantyl)-8-methoxy-1-naphthol.
A sequential Diels–Alder reaction of furan and arynes generated
from 1,2-bromotriflates provided tricyclic and tetracyclic epoxides,
and acid-catalyzed aromatization gave phenanthrol and chrysenol. Deoxygenation
reactions involving the hydrogenolysis of triflates gave 1,8-bisÂ(1-adamantyl)Ânaphthalene,
1,10-bisÂ(1-adamantyl)Âphenanthrene, and 1,12-bisÂ(1-adamantyl)Âchrysene.
3,4-BisÂ(1-adamantyl)Âpyrene was synthesized from phenanthrol by Sonogashira
coupling and Pt-catalyzed cyclization. Essentially no racemization
occurred during the synthesis. X-ray analysis indicated the distorted
naphthalene moiety possessing the peri-diadamantyl groups and the
flat structure of the other benzene rings. UV–vis analysis
of the equatorenes showed considerable redshifts compared with that
of the corresponding achiral arenes. Electrochemical analysis of the
naphthalene and pyrene indicated that the distortion decreased the
highest occupied molecular orbital stability with no marked effect
on the lowest unoccupied molecular orbital energy level, and the origin
was discussed on the basis of calculation results