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981.
[reaction: see text] Reaction of an enoate bearing an epoxysilane moiety at the alpha-position with lithium enolate of 2-chloroacetamide afforded highly functionalized cyclopropane derivatives via a tandem process that involves Michael addition, ring opening of the epoxide, Brook rearrangement, and intramolecular alkylation. 相似文献
982.
[Structure: see text] A 1,4-bis(phenyl)-1,4-dihydro[60]fullerene resulting from an efficient nucleophilic substitution has been obtained by reaction of a fullerene epoxide, C60O, with nucleophilic aromatic compounds in the presence of boron trifluoride etherate as a Lewis acid. 相似文献
983.
Sasaki T 《Chemical record (New York, N.Y.)》2006,6(1):43-51
This paper reviews our recent work on the photorefractive effect of ferroelectric liquid crystals (FLCs). The photorefractive effect is defined as the optical modulation of the refractive index of a medium as a result of a variety of processes. The interference of two laser beams in a photorefractive material establishes a refractive index grating. This phenomenon enables the creation of different types of photonic applications. FLCs exhibit fast electric field response, and the orientation of the molecular axis of FLCs changes its direction according to the change in direction of the spontaneous polarization (Ps). When two laser beams interfere in a photoconductive FLC, an orientational grating is formed. The mechanism of the formation of the grating is based on the response of the Ps to the photoinduced internal electric field. The time of formation of the refractive index grating is significantly shorter in FLC materials. 相似文献
984.
Ohmori K Katsuki H Chiba H Honda M Hagihara Y Fujiwara K Sato Y Ueda K 《Physical review letters》2006,96(9):093002
The quantum interference of two molecular wave packets has been precisely controlled in the B electronic state of the I2 molecule by using a pair of fs laser pulses whose relative phase is locked within the attosecond time scale and its real-time evolution has been observed by another fs laser pulse. It is clearly observed that the temporal evolution changes drastically as a function of the relative phase between the locked pulses, allowing us to read both amplitude and phase information stored in the wave functions of the molecular ensemble. 相似文献
985.
986.
Yusuke Kosaki 《Tetrahedron letters》2010,51(14):1856-89
Resolvin E2 (2) was synthesized stereoselectively using the C1-8 and C15-20 aldehydes 6 and 9, which were connected to the C9-14 fragment by using Wittig reactions. The aldehyde 6 was prepared from the γ-silyl alcohol (S)-20 by a sequence of reactions involving ozonolysis, oxidation with NaIO4, and the Wittig reaction of the resulting aldehyde with Ph3PCHCHO, whereas the aldehyde 9 was synthesized from the corresponding γ-silyl alcohol through epoxidation, reaction with Et2AlCN, and reduction with DIBAL-H. 相似文献
987.
Yusuke Ogura 《Tetrahedron letters》2010,51(25):3294-7102
A model compound (6) with the core skeleton of lysidicin A was synthesized as a racemate. The key step (8→7) includes three Claisen rearrangements of the triether with phloroglucinols; two of which rearranged in a cascade manner and the other was a simple rearrangement. This one-pot reaction enabled the introduction of three phloroglucinol units at the correct positions and makes the synthetic approach significantly efficient. 相似文献
988.
Kou Hiroya Yusuke Ichihashi Yoshihiro Suwa Tetsuro Ikai Kiyofumi Inamoto Takayuki Doi 《Tetrahedron letters》2010,51(29):3728-3731
The C2-side chain hydroxyl group of 1,3-cycloalkanedione discriminates between two ketones depending on its chirality. It chooses one ketone to form hydrogen bond with the oxygen atom of the TBDPS-oxymethyl group, but chooses the other ketone upon conversion to the isopropyl acetal. Two optically pure diastereomers, whose absolute configuration at the angular position is opposite for each other, were thus synthesized from this single chiral source through simple operations. This method may be applied for the synthesis of a variety of compounds with asymmetric quaternary centers. 相似文献
989.
990.
The visible-light-induced photocatalytic conversion of aqueous benzene to phenol on Au-nanoparticle-supported layered titanate was accelerated when the reaction was conducted in the presence of aqueous phenol. 相似文献