Annulated 1,3,4-Azadiphospholides: Heterocycles with Widely Tunable Optical Properties.

Suter, Riccardo; Benkő, Zoltán; Bispinghoff, Mark; Grützmacher, Hansjörg

Phosphorus heterocycles find applications in the synthesis of π-conjugated compounds and as precursors for optoelectronic materials such as organic light-emitting diodes (OLEDs), electronic switches, and transistors. A high-yield, one-pot synthesis of anionic annulated 1,3,4-azadiphospholides from Na(OCP) and 2-chloropyridines is presented. The synthesis proceeds without the use of transition metals and tolerates a wide range of substrates. Cyano-substituted compounds are especially deeply colored and have absorption maxima which range from λmax=525 to 596 nm. The optical properties are dominated by the spatial separation of an electron acceptor and donor unit within one molecule (push-pull chromophore). The anionic 1,3,4-azadiphospholides are silylated to neutral siloxy compounds with a strong blue-shifted absorption. This reaction can be reversed by addition of fluoride ions, which allows fluoride ions to be detected in optically low concentrations.

HETEROCYCLIC compounds; OPTICAL properties of metals; ANNULATION; OPTOELECTRONICS; AZA compound synthesis; ORGANIC light emitting diodes

Angewandte Chemie, 2017, Vol 129, Issue 37, p11378

0044-8249

Academic Journal

10.1002/ange.201705473