Affiliation:
1. Institute of Organic Chemistry II and Advanced Materials Ulm University Albert-Einstein-Allee 11 89081 Ulm Germany
2. Department of Chemistry – Ångström laboratories Uppsala University BOX 523 75120 Uppsala Sweden
3. Helmholtz Institute Ulm Karlsruhe Institute for Technology Helmholtzstrasse 11 89081 Ulm Germany
Abstract
AbstractStarting from two different cyano‐functionalized organoboranes, we demonstrate that 1,3‐dipolar [3+2] azide‐nitrile cycloaddition can serve to generate libraries of alkyl‐tetrazole‐functionalized compounds capable of intramolecular N→B‐Lewis adduct formation. Due to the relatively low basicity of tetrazoles, structures can be generated that exhibit weak and labile N→B‐coordination. The reaction furnishes 1‐ and 2‐alkylated regio‐isomers that exhibit different effective Lewis‐acidities at the boron centers, and vary in their optical absorption and fluorescence properties. Indeed, we identified derivatives capable of selectively binding cyanide over fluoride, as confirmed by 11B NMR. This finding demonstrates the potentialities of this synthetic strategy to systematically fine‐tune the properties of lead structures that are of interest as chemical sensors.
Funder
Deutsche Forschungsgemeinschaft
Fonds der Chemischen Industrie
Vetenskapsrådet