Synthesis of Green/Blue Light Emitting Quinolines by Aza-D-A Reaction Using InCl3 Catalyst.

An efficient InCl3-catalyzed sequential reaction of aromatic amines, aromatic aldehydes and functionalized alkynes leading to the formation of new quinoline derivatives exhibiting significant fluorescence activities is described. The photophysical investigations of quinolines were carried out by absorption and photoluminescence measurements. One particular compound 4 h having maximum intensity, emitting green colour (Φ = 0.78) with average life time of 6.20 ns was the best amongst the tested compounds. The presence of the amino group at the 4-aryl substituent of the quinoline backbone played an important role in executing the Povarov cyclization successfully and enhancing the flourescence properties of the newly synthesized quinolines.

Alkyne functionalized cellulose fibers: A versatile "clickable" platform for antibacterial materials.

We report a facile and effective method to fabricate clickable alkyne-functionalized cellulose fibers (ACFs) through in situ chemical oxidation copolymerization of 3-ethynylaniline and aniline under acidic aqueous solution. The effects of process variables on copolymer deposition onto CFs were investigated and suitable preparation conditions were identified. It was found that aniline significantly facilitated the polymerization of 3-ethynylaniline and shortened the preparation time of ACFs from 48 to 6 h. Antibacterial-modified cellulose fibers were prepared by binding ß-cyclodextrin (ß-CD) to cellulose fibers via click chemistry, followed by the inclusion of ciprofloxacin hydrochloride (CipHCl). The loading and releasing behaviors of CipHCl into/from click product (ACFs@Azide-ß-CD) were also revealed. The load amount of CipHCl into ACFs@Azide-ß-CD increased remarkably, and the release of CipHCl from ACFs@Azide-ß-CD was prolonged. The ACFs@Azide-ß-CD loaded with CipHCl exhibited higher and longer-term antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureu) compared with CFs and ACFs.

Grafting Behavior for the Resonating Variants of Ethynylaniline on Hydrogenated Silicon (100) Surfaces under Thermal Hydrosilylation.

This work reports the outcome of thermal grafting of 2-ethynylaniline, 3-ethynylaniline, and 4-ethynylaniline on a hydrogenated Si(100) surface. Using high-resolution XPS and AFM, it was found that the grafting of these compounds could be attributed to resonating structures that arise from the position of an electron-donating NH2 group and an electron-withdrawing acetylene group. For the ortho- and para-positioned acetylene group, surface reactions were observed to proceed predominantly via the acetylene to form a Si-C bond, whereas the meta-positioned acetylene group was found to have undergone nucleophilic grafting through the NH2 group onto the silicon surface to form a Si-N bond. Furthermore, a tert-butoxycarbonyl-protected derivative for a meta-positioned ethynylaniline was synthesized to exclusively force the reaction to react with the acetylene group and subsequent analysis confirmed that unprotected 3-ethynylaniline had indeed reacted through the nucleophilic NH2 group as hypothesized. Thus, for the first time, the interplay between resonance structures and their effects on silicon surface modifications were systematically catalogued.