A convenient method for the synthesis of alpha-ethynylphospholes and modulation of their pi-conjugated systems

Angew Chem Int Ed Engl. 2009;48(22):4002-5. doi: 10.1002/anie.200900542.

Abstract

Mind the (narrow) gap: Alpha-ethynylphospholes generated in situ from the corresponding silyl-capped precursors were converted into a series of alpha-(arylethynyl) phospholes bearing functional substituents as well as an alpha,alpha'-linked terphosphole (see scheme). The terphosphole has a narrow HOMO-LUMO gap owing to efficient pi conjugation over the three phosphole rings.