187662-48-2Relevant academic research and scientific papers
Orthogonal switching of self-sorting processes in a stimuli-responsive library of cucurbit[8]uril complexes
Schoder, Stefan,Schalley, Christoph A.
, p. 9546 - 9549 (2017)
The self-sorting processes in dynamic libraries of cucurbit[8]uril complexes can be switched in an orthogonal way by external stimuli. Protonated phenylpyridine guests form a 2:1 homoternary π-donor-π-acceptor complex, while deprotonation makes it a partner for ethylviologen in a 1:1:1 heteroternary complex. Reduction of the viologen instead generates a 2:1 homoternary complex of viologen radical-cations.
Dimerization of terminal arylalkynes in aqueous medium by ruthenium and acid promoted (RAP) catalysis: Acetate-assisted (sp)C-(sp2)C bond formation
Coniglio, Alessandra,Bassetti, Mauro,Garcia-Garrido, Sergio E.,Gimeno, Jose
supporting information; experimental part, p. 148 - 158 (2012/03/27)
The hexamethylbenzene ruthenium(II) dimer [{RuCl(m-Cl)(h6-C 6Me6)}]2 (5 mol%), tested among a series of ruthenium(II) and ruthenium(IV) complexes, represents an efficient precatalyst source for the dimerization of terminal arylalkynes ArCΞ CH [Ar=C 6H5, 3,4,5-(OMe)3C6H2, 4-MeOC 6H6, 2-MeOC6H6, 4-MeC 6H6, 2,4,5-Me3C6H2, 4-BrC 6H6, 4-ClC6H6, 4-FC 6H6, 4-HC(=O)C6H6, 4-CH 2=CHC6H6, 3-NCC6H6, 4-O2NC6H6, 4-EtO2C-(CH2)3OC6H 6, 4-HO(CH2CH2O)3C6H 6, 3-HO(CH2CH2O)3-C 6H6] in acetic acid/water mixture (1:1, v/v). The reactions proceed for 24 h at room temperature under heterogeneous conditions and afford the dimeric enyne derivatives (E)-Ar-CH=CH-C-C-Ar in high yields and stereoselectivity. The preformed acetato complex [RuCl(h6-C 6Me6)(k2-OAc)] catalyzes the dimerization of phenylacetylene under analogous conditions, with rapid substrate conversion. The presence of cosolvents of acetic acid different from water reduces dramatically the efficiency and selectivity of the reaction. The aqueous medium facilitates the activation stage of the precatalyst by assisting the splitting of the ruthenium dimer. The addition or generation in situ of acetate salts results in shorter reactions times (0.5-3 h) and excellent yields, due to the rapid formation of active acetato complexes. Circumstantial evidence indicates that the p-bound alkyne molecule is activated by intramolecular proton abstraction. This is currently the most efficient, E-selective and wide-scope catalytic system for the alkyne dimerization reaction in protic aqueous media.
Host-Guest complexation-triggered chiroptical change of poly(phenylacetylene)s bearing binaphthocrown ether moieties on the main chain
Ryosuke, Sakai,Takafumi, Yonekawa,Issei, Otsuka,Ryohei, Kakuchi,Toshifumi, Satoh,Toyoji, Kakuchi
experimental part, p. 1197 - 1206 (2010/11/18)
Diacetylene monomers with respective lengths of the oxyethylene chains were cyclopolymerized with a rhodium catalyst to produce novel poly(phenylacetylene) s bearing a different cavity size of the chiral crown ether in the repeating units (2a-c), In the c
Quick assembly of 1,4-diphenyltriazoles as probes targeting β-amyloid aggregates in Alzheimer's disease
Qu, Wenchao,Kung, Mei-Ping,Hou, Catherine,Oya, Shunichi,Kung, Hank F.
, p. 3380 - 3387 (2008/02/08)
Accumulation of β-amyloid aggregates (Aβ) in the brain is linked to the pathogenesis of Alzheimer's disease (AD). We report a novel approach for producing 1,4-diphenyltriazoles as probes for targeting Aβ aggregates in the brain. The imaging probes, a seri
New diphenylacetylenes as probes for positron emission tomographic imaging of amyloid plaques
Chandra, Rajesh,Oya, Shunichi,Kung, Mei-Ping,Hou, Catherine,Jin, Lee-Way,Kung, Hank F.
, p. 2415 - 2423 (2008/02/05)
A series of 18F fluoropegylated diphenylacetylenes as probes for binding to Aβ plaques were successfully prepared. These relatively rigid acetylenes, 12a, 12b, 14a, and 14b, displayed high binding affinities in postmortem AD brain homogenates (
