Synthesis and reactions of Janus-type bis(NHCs), tuned by phosphorus bridges

Abstract

Due to our first attempts to synthesize P-functional bis(NHCs),[6] we were aware of a problem if bis(thiones) were used. Therefore, the idea emerged to use bis(selones) instead. Herein, the synthesis of the first tricyclic bis(selones) and their conversion to bis(NHCs) having two facially opposed imidazole-2-ylidenes with two linking phosphorus centers in different oxidation states is presented. Furthermore, the formation of homo-bimetallic metal(I) complexes of these NHCs as well as reactions with reducing agents are reported.