Preparation and Photochemistry of Dendrimers with Isolated Stilbene Chromophores

Abstract

Keywords: Crosslinking / Cyclization / Dendrimers / IsomerizationIn addition to the model compounds 4a and 4b, the dendrimers 11 and 14 with trans-stilbene chromophores in the core and on the periphery of the dendrons were prepared and their photochemistry was studied in solution and in neat films. Due to the flexibility of the arms, intramolecular and intermolecular CC bonds are formed on irradiation. Thus, the generation of nanoparticles, which represent small oligo-

Naphthyridine tetramer with a pre-organized structure for 1:1 binding to a CGG/CGG sequence

“…Synthesis of NCT ( 22 ) and Z -NCTS was achieved by reductive amination of glutaraldehyde and ( Z )-4,4′-diformylstilbene ( 47 ), respectively, with the secondary amino group of NCD ( Scheme 1 ). NCTB and E -NCTS were synthesized from 3,3′-bis(bromomethyl)biphenyl ( 48 ) and ( E )−4,4′-bis(bromomethyl)stilbene ( 49 ) using a nucleophilic substitution reaction with two NCD molecules. NT, where naphthyridines are connected with amide linkages instead of carbamate linkages in NCD, was synthesized as reported previously ( 21 ).…”

“…To a solution of NCD (150 mg, 0.30 mmol) in anhydrous DMF (4 ml) were added ( E )−4,4′-dibromomethylstilbene ( 49 ) (24 mg, 0.065 mmol) and stirred at ambient temperature for 2.5 h. The reaction mixture was diluted with saturated NaHCO 3 and extracted with AcOEt. The organic phase was successively washed with water and brine, dried over MgSO 4 , filtered, and evaporated in vacuo .…”

Supramolecular order of stilbenoid dendrons: importance of weak interactions

“…4,5,37 Photopolymerisation and crosslinking of stilbenoid compounds in thin films could be nicely pursued by AFM measurements. 38 The photosensitivity has also been investigated in the neat condensed phases of mesogen 3e by means of POM (Fig. 12).…”

Stilbene-cored poly(glutamate) dendrimers

“…In this area, the photoisomerization of dendrimers with photoresponsive cores-such as stilbene, [13][14][15][16][17][18][19][20][21] azobenzene, [22][23][24][25][26][27][28][29][30][31][32][33] diarylethene, [34][35][36][37][38] intramolecularly hydrogen-bonded chromophores, [39][40][41] and photolabile chromophores 42-44 -has been extensively investigated. We recently reported that stilbene dendrimers with benzyl ether-type dendrons exhibited a volume-conserving isomerization mechanism and a macromolecular effect (or generation effect) on energy transfer efficiency from the peripheral dendrons to the core stilbene in organic solvents [45][46][47] and aqueous solution.…”