Fischer’s carbene

Mo and W catalysts used by other researchers for the polymerization of acetylenes are shown in Table 7. They are all organometallics, and are usually less active than those in Table 3. It is reported that ladder polymers form from acetylenes in the presence of the toluene Mo(CO)3 complex 8). Katz and Lee have succeeded in polymerizing acetylenes with Fischer s carbene (3 a) and Casey s carbene (3b)9) ... 

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