186663-74-1Relevant articles and documents
Water-soluble polymeric probe with dual recognition sites for the sequential colorimetric detection of cyanide and Fe (III) ions
Gupta, Moumita,Lee, Hyung-il
, p. 174 - 180 (2019)
A water-soluble polymeric probe derived from an azo-Schiff base was developed for the consecutive colorimetric sensing of CN? and Fe3+ ions in water. Herein, the synthesis of a random copolymer of N,N-dimethylacrylamide (DMA) and 3-vinylbenzaldehyde (VBA) via reversible addition-fragmentation chain transfer polymerization, [p(DMA-co-VBA, P1] is described. A post-polymerization modification reaction between the aldehyde groups of P1 and (E)-2-amino-4-((4-nitrophenyl)diazenyl)phenol in ethanol led to the target polymer, P2, with azo-Schiff base moieties. The colorimetric detection of CN? ions occurred because of the abstraction of phenolic proton of P2 by the CN? ions to form hydrazone, which was accompanied by the color change from brick-red to purple. The selective colorimetric detection of Fe3+ ions with P2 over other cations in water was also observed via the formation of a coordination complex between Fe3+ ions and azo-Schiff base ligands of P2. After the individual detection of CN? and Fe3+ was carried out, consecutive sensing studies were performed. Although Fe3+ was sequentially observed after the presence of CN? ions was noted, detection using a reverse sequence from Fe3+ to CN? was not possible because of the intense color of the resulting P2[sbnd]Fe3+ complexes, which suppressed any observable color changes typically caused by the formation of hydrazone.
Synthesis of 3-substituted and 2,3-disubstituted-4H-1,4-benzoxazines
Buon,Chacun-Lefèvre,Rabot,Bouyssou,Coudert
, p. 605 - 614 (2000)
Two new and efficient synthetic routes towards substituted 4H-1,4- benzoxazine derivatives were reported. The first one involves the synthesis in four steps of the 4-Boc-4H-1,4-benzoxazine and its regioselective substitution on C-3 following a lithiation-
Functionalizable red emitting calcium sensor bearing a 1,4-triazole chelating moiety
Collot, Mayeul,Wilms, Christian,Mallet, Jean-Maurice
, p. 6993 - 7000 (2015)
Herein we developed a functionalizable OFF-ON red emitting fluorescent calcium probe based on a new chelating system formed by CuAAC click chemistry (Huisgen cycloaddition). The pro-sensor 7 which is not sensitive to Ca2+, contains an alkyne moiety that, upon the click reaction, forms a chelating group involving the 1,4-triazole. Probe 10 exhibited good sensitivity towards calcium (Kd = 5.8 μM) and zinc (5.6 μM) with a high dynamic range (65 fold fluorescence increase), high quantum yield (0.59) and showed very low fluorescence enhancement in the presence of a high concentration of Mg2+. We extended this method and generated two dextran conjugates in order to compare their sensing properties with those of the molecular form of 10.
A mild and metal-free synthesis of chiral 2,3-dihydro-3-hydroxymethyl-1,4-benzoxazines
Cheng, Shihao,Huang, Haihong,Li, Shengnan,Lin, Ziyun,Zhang, Dongfeng,Zhao, Hongyi
, (2021/07/06)
Various functionalized enantiomerically pure 3-hydroxymethyl-1,4-benzoxazine derivatives, including four stereoisomers, were synthesized from chiral 2,3-epoxy-4-trityloxybutanol. The synthesis was mild and metal-free. Yields of 52%–94%, and stereoselectiv
Switchable Oxidative Reactions of N-allyl-2-Aminophenols: Palladium-Catalyzed Alkoxyacyloxylation vs an Intramolecular Diels-Alder Reaction
Beccalli, Egle M.,Giofrè, Sabrina,Keller, Manfred,Lo Presti, Leonardo,Molteni, Letizia
supporting information, p. 7698 - 7702 (2021/10/25)
The Pd(II)-catalyzed reaction of N-allyl-2-aminophenols in the presence of PhI(OCOR)2 as the oxidant resulted in an alkoxyacyloxylation process, with the formation of functionalized dihydro-1,4-benzoxazines. The reaction performed in the absence of pallad
