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A coaxial nanohybrid consisting of a single-walled carbon nanotube (SWCNT), fullerodendron, and SiO(2) shows high-efficiency light-driven hydrogen evolution from water. Upon visible light irradiation, SWCNT/fullerodendron/SiO(2) coaxial nanohybrid shows hydrogen evolution activity in the presence of methyl viologen (MV(2+)), benzyldihydronicotinamide (BNAH), and a colloidal polyvinyl alcohol(PVA)-Pt., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new poly(amidoamine) dendron having 1,5-diazabicyclo[4.3.0]non-5-ene (DBN) at the focal point was synthesized. Interestingly, formation of zwitterionic fullerodendrons (λ(max) = 930 nm for C(60) and 795 nm for C(70)) were observed by Vis-NIR spectroscopy upon the reaction of C(60) or C(70) with the DBN-focal dendron. In particular, the C(70) anion was effectively stabilized by the site isolation effect of the dendritic wedge. The half-life of fullerodendron 12b having C(70) anion at the focal point reaches 7,345 min, which is 20 times longer than that of complex between C(60) and pristine DBN. Furthermore, in order to confirm the structure of the zwitterionic complex, fullerodendron 12a was reprecipitated from benzonitrile/1,2,4-trimethylbenzene, and was observed using IR spectroscopy and APPI-MS.

Photoinduced charge separation of fullerodendrimers with carboxylates at terminal sites (C60 approximately COO-) has been found in aqueous media. Time-resolved transient absorption and fluorescence measurements of the fullerodendrimers demonstrated that charge separation takes place from the terminal carboxylate anion to the central excited singlet state of C60, generating C60*- approximately COO* with high quantum efficiency in aqueous solution. In the presence of viologen dication and a sacrificial donor, the persistent viologen radical cation was generated.

Hydrogen gas, which can be used in fuel cells to generate electricity, is considered the ultimate clean energy source. Recently, it was reported that a photo-induced electron transfer system consisting of single-walled carbon nanotubes (SWCNTs) and fullerodendrons shows photo-catalytic activity with a very high quantum yield for splitting water under visible light irradiation. However, the mechanism of high efficiency hydrogen generation is not yet clearly understood. We report here the spectroscopic characterizations of the SWCNT-fullerodendron composites. The results indicate two important fundamental properties of the composite system. First, fullerodendrons preferentially interact with the semiconducting SWCNTs instead of with their metallic counterparts. Second, the photo-induced electron transfer process from the C60moiety of fullerodendrons to SWCNTs occurs more efficiently with an increasing tube diameter. [ABSTRACT FROM AUTHOR]

Water-soluble fullerodendrimer was obtained by the use of a Diels–Alder reaction of C60 with a newly designed anthryl dendron under an extremely mild condition in 70% yield, which is more than five times as high as the yield described in our previous report. [Copyright &y& Elsevier]

Spherical silver nanoparticles (diameter: 7-10nm) were fabricated through passivation by fullerodendrons (C60(GnCOOK) (n = 0.5, 1.5, 2.5)), which were synthesized from fullerene and anthracenyl focal poly(amido amine) dendrons with carboxylate terminals and different generations (G). The resultant nanocomposites presented unique luminescence, which was contributed by not only anthracenyl moiety but also poly(amido amine) dendron moiety, although the latter has no traditional fluorophore. Furthermore, fluorescence of C60(G2.5-COOK) was quenched by the silver nanoparticles, indicating that the excitation energy transferred to silver particles. [ABSTRACT FROM AUTHOR]

Light illumination of single-wall carbon nanotubes (SWCNTs) dispersed with anthracene (An) dendrons afforded the accumulation of the reduced form of methyl viologen in the presence of a hole shifter. With the helps of the fluorescence lifetime and transient absorption measurements, the charge-separation process from the excited state of the hybrides of An dendrimer to SWCNT was confirmed. [ABSTRACT FROM AUTHOR]

Abstract: The Diels–Alder reaction between C60 and anthryl glycodendron, which has d- or l-gluconamides at the terminals, gave a new fullerene glycodendron conjugate. Interestingly, the diastereoselective cycloaddition reaction proceeded upon the treatment of C60 with the anthryl dendron 3. Furthermore, optical pure fullerodendrons (−)-4L and (+)-4D, which were confirmed by 1H and 13C NMR spectroscopy, FT-IR, MALDI-TOF mass spectroscopic analysis, were isolated from the mixture of diastereomers. And their absolute configurations were predicted by the use of CD spectra. [Copyright &y& Elsevier]

The first isolation of a single pure regioisomer of a C70-acene monoadduct is reported. [ABSTRACT FROM AUTHOR]