Cinnamoyl shell-modified poly(amidoamine) dendrimers

Abstract

Poly(amidoamine)(PAMAM) dendrimers with a cinnamoyl shell were prepared by reacting full generation PAMAM dendrimers (Gϭ3.0) with 2-chloroethanol and cinnamoyl chloride, which resulted in densely packed polymerizable unsaturated groups on the periphery. The cinnamoyl shell of the dendrimers dimerized when irradiated under a UV light by using 5-nitroacenaphthylene as an initiator in dilute dimethylformamide (DMF). FTIR, 1 H NMR, UV-Vis, SEC, and a viscosity test certified that the photocycloaddition of the cinnamoyl shell of the dendrimers took place within the molecules with the disappearance of double bond signals in the FTIR. 1 H NMR spectra as well as the intrinsic viscosity and polydispersity value of the products both before and after irradiation showed no difference. It was further found that the cinnamoyl shell-modified dendrimers possessed fluorescence property, and the fluorescence intensity became stronger when the shell was photocyclized under UVirradiation.

Liquid crystalline photoactive hyperbranched and linear benzylidene polyester with terminal epoxy and pendant hydroxyl groups

“…7 Limited availability of AB n monomers increases the use of readily available A 2 þ B 3 monomers for the synthesis of HBP. 8,[9][10][11] After preliminary work by Kim 12 on hyperbranched liquid crystalline polymers, (HBLCPs), synthesized by the AB n approach, the revolutionary work in this field was carried out by Percec et al, [13][14][15][16][17][18] Shibaev et al, 19 and others [20][21][22][23] have reported on photo-addressable dendritic polymers (PADLCPs) containing both mesogenic and photochromic groups. PADLCPs have shown enhanced physicochemical properties and photo and thermally induced physical changes as compared with linear polymers.…”

Synthesis of a novel star polymer consisting of a dendritic polyamidoamine core and polystyrene arms and its self‐assembly to form large multimolecular micelles

“…PAMAM–OH was prepared with a modified literature method 34, 35. Typically, in a three‐necked, round‐bottom flask equipped with a thermometer, dropping funnel, and magnetic stirrer, 4 g (0.0028 mol) of a PAMAM dendrimer of two generations was dissolved in 100 mL of DMF, and then 3.63 g (0.0448 mol) of chlorohydrin was added dropwise under vigorous stirring at room temperature for 30min.…”

Architecture of stable and water-soluble CdSe/ZnS core–shell dendron nanocrystals via ligand exchange

“…Boc-G3.0 was modified by one-step reactions with chlorohydrin to obtain Boc-G3.0-OH using a modified literature method [23,24]. Typically, in a 3-neck round bottomed flask equipped with a thermometer, dropping funnel and magnetic stirring, Boc-G3.0 (8 g) of two generation was dissolved in DMF (100 mL), and then, chlorohydrin (6 g) was added dropwise under vigorous stirring at room temperature for 30 min.…”