Publication detail

Malonic Acid Derivatives on Duty as Electron-Withdrawing Units in Push-Pull Molecules

Year: 2017

Type of publication: článek v odborném periodiku

Name of source: European Journal of Organic Chemistry

Publisher name: Wiley-VCH

Place: Weinheim

Page from-to: 2764-2779

Titles:

Language	Name	Abstract	Keywords
cze	Deriváty malonové kyseliny jako elektronakceptorní jednotky v push-pull molekulách	Bylo připraveno 32 push–pull molekul s 2-(N-piperidinyl)thiofenem jako centrálním donorem a systematicky obměňovaným akceptorem na bázi malonové kyseliny. Další vlastnosti byly modifikovány s využitím různých pi-linkerů a strukturním uspořádáním derivátů (lineární nebo kvadrupolární D-pi-A systém). Jako akceptorní jednotky byly využity zmiňované strukturní analogy malonové kyseliny jako kyanoctová kyselina, malondinitril, diethyl-malonát, Meldrumova kyselina, N,N'-dibutyl(thio)barbiturová kyselina, dimedon a indan-1,3-dion. Knoevenagelovou kondenzací se čtyřmi thiofenkarbaldehydy byly připraveny cílové chromofory v uspokojivých výtěžcích. Elektronakceptorní schopnosti akceptorů byly posuzovány X-ray analýzami, diferenční skenovací kalorimetrií, elektrochemicky, UV/Vis absorpčními spektry a DFT kalkulacemi.	Donor-akceprotní systémy; chromofory; vztahy struktura-aktivita; přenos náboje; elektronakceptorní schopnost
eng	Malonic Acid Derivatives on Duty as Electron-Withdrawing Units in Push-Pull Molecules	Based on the 2-(N-piperidinyl) thiophene central donor, 32 model push-pull molecules with systematically varied malonic acid-derived peripheral acceptors have been prepared. Further property tuning has been achieved by modifying the p-linker and the structural arrangement (linear vs. quadrupolar D-p-A systems). Malonic acid derivatives such as cyanoacetic acid, malondinitrile, diethyl malonate, Meldrum's acid, and N, N'dibutyl(thio) barbituric acid as well as 1,3-diketo analogues dimedone and indan-1,3-dione were employed as acceptor moieties. Knoevenagel condensation with four thiophene aldehydes afforded the target chromophores in satisfactory yields. The electron-withdrawing abilities of malonic acid acceptors were examined both by experiment including X-ray analysis, differential scanning calorimetry, electrochemistry, and UV/Vis absorption spectroscopy, and by DFT calculations. Details of the structure- property relationships have been elucidated. According to the increasing electron-withdrawing ability, the widely used malonic acid acceptor units can be ordered: diethyl malonate <= cyanoacetic acid < malondinitrile < Meldrum's acid < dimedone <= N, N'-dibutylbarbituric acid < indan-1,3-dione <= N, N'-dibutylthiobarbituric acid.	Donor-acceptor systems; Chromophores; Structure-activity relationships; Charge-transfer; Electron-withdrawing strength

Search

Login for students

Login for employees

Publication detail

Departments

Other Parts

Map

Services

Popular Links