Novel π-electron systems derived from silicon-containing macrocyclic polyacetylenes
Disilmethylene bridged cyclic Iriacetylene and tetraacetylene are prepared and subjected the transition metal complex mediated reactions. In particular, the reaction with (cyc1opentadienyl)txicarbonylmanganese gave a variety of cross-conjugated systems such as lulvene, dimethylenecyclobutene, trimethylenecyclopenkne and radialene. Structures and reactions of these interesting x-electron systems are described. Dianions derived from these systems are also discussed briefly.