An Efficient Method for the Programmed Synthesis of Multifunctional Diketopyrrolopyrroles. (17th March 2020) - Pieczykolan, Michał
Abstract: A new, transformative methodology for the preparation of diketopyrrolopyrroles from aldehydes, primary amines, nitriles, and diethyl oxalacetate has been developed. It is now possible to prepare diketopyrrolopyrroles bearing an ordered arrangement of three different substituents from abundant and commercially available materials, allowing the independent regulation of all desired physicochemical properties. For the first time very electron‐rich (carbazol‐3‐yl, dimethylaminophenyl, pyrrolo[3, 2‐ b ]pyrrolyl), and sterically hindered substituents (naphthalen‐1‐yl, quinolin‐4‐yl, acridin‐9‐yl, imidazo[1, 5‐ a ]pyridin‐1‐yl, 2‐bromophenyl etc.) can be appended to the diketopyrrolopyrrole core by condensation of an appropriate nitrile with a pyrrolidin‐2‐one intermediate. Even greater synthetic possibilities are related to the fact that such demanding substituents as 4‐dimethylaminophenyl, indol‐3‐yl, and 2‐methoxyphenyl can be incorporated from aldehyde precursors, bypassing problems with the nitriles reactivity. Abstract : Freie Farbauswahl : Ein neuer Ansatz zur Synthese von Diketopyrrolopyrrolen mit Elektronendonor‐ sowie sterisch eingeschränkten Substituenten wurde entwickelt. Er erlaubt die regioselektive und programmierte Anbringung von C ‐Aryl und N ‐Alkyl‐Substituenten. Beispiellose Kontrolle über die optischen Eigenschaften wurde in der Synthese einer Vielzahl dipolarer DPP‐Derivate gezeigt, die teilweise bislang unzugängliche Substituenten enthalten.