Synthesis of 8-aminoquinoline chelating moieties for chemosensor molecules

Abstract

8-Aminoquinolines are useful molecular motifs for ion sensors. To encourage chemosensor development, new building blocks containing these motifs are essential. 8-Aminoquinoline-2-carbaldehydes are proposed as useful building blocks since their aldehyde group offers the possibility for further transformations. We present a general method for the preparation of these compounds starting from commercially available 8-bromo-2methylquinoline. Different sidechains for fine-tuning their affinity and selectivity were introduced by a microwave-aided N-arylation using Pd(0) and P-ligands; the desired products were achieved by oxidation. An alternative method is also presented when the product shows high affinity towards the catalyst limiting the effectiveness of the Pd-catalysed the N-arylation.

3-Aminopropylazetidines: facile synthesis and application for medicinal chemical purposes

“…In the course of our ongoing studies on fluorescent dyes and fluorescent turn-on probes for various metal ions, [1][2][3][4] we were interested in the synthesis of novel chemical tools with an aminoquinoline heterocycle as the metalcomplexing scaffold (Scheme 1). Out of the various amine side chains, the 3-(azetidin-1-yl)propan-1-amine moiety is used in a number of potentially pharmacologically-active molecules, described mainly in the medicinal chemistry patent literature.…”

“…Selected examples of aminoquinoline derivatives used for the synthesis of metal sensors. 4 Scheme 2. Examples of the 3-(azetidin-1-yl)propan-1-amine moiety in medicinal chemistry.…”