complexes bearing ester functions at the periphery of the ligands are shown to be efficient fluorescent chemosensors for picricacid detection. The prominent role of an association between the chemosensor and the picricacid in the detection process is demonstrated. The detection of picricacid in water is achieved with the sensor deposited on paper.
A series of AlIII complexes of a salophen (N,N′-bis(salicylidene)-o-phenylenediamine) derivative with an ester substituent at the C5 position of the salicylidene rings have been prepared and their luminescence properties investigated. All exhibit a bright blue emission (λem = 478 nm) that is observed neither for other metal ions nor with the non-functionalized ligand. Moreover, the ester-R group (Me, tBu, Ph) was found to significantly affect the quantum yields (ϕ = 12 to 20%) of the luminophor. DFT calculations have been undertaken to reveal the influence of the ester and its R-group on the frontier molecular orbitals. Preparation and photoluminescence properties in solution and solid state are reported. The crystal structure of a pyridine oxide adduct [LtBuAl(PyO)2]·NO3, where LtBu stands for the tButyl-ester functionalized Schiff base, has been solved.
Oxidative Dearomatization: Synthesis of Functionalized Bicyclo[2.2.2]octenones, Sigmatropic Shift in Excited State, and Radical-Induced Cleavage of Cyclopropane Ring
作者:Karan Arora、Vishwakarma Singh
DOI:10.1080/00397911.2014.941502
日期:2014.12.17
Abstract Synthesis of novel bicyclo[2.2.2]octenones endowed with a β,γ-enone system in which γ-carbon is substituted with an electron-withdrawing group from simple aromatics is described. Oxa-di-pi-methane reaction of bicyclo[2.2.2]octenones to functionalized bicyclo[3.3.0]octanes and their transformation to bicyclo[3.2.1]octane framework are also presented. GRAPHICAL ABSTRACT