Catalysts for Diyne Metathesis

点击翻译按钮获取中文摘要

Alkyne metathesis, i.e. the reversible cleavage and formation of carbon-carbon triple bonds, has gained increasing importance in recent years through the development of efficient catalysts in organic synthesis, supramolecular chemistry, and materials science. For the related metathesis of conjugated diynes, however, only a few catalysts exist so far. Building on the results of the previous proposal, new diyne metathesis catalysts will be developed and used in transformations such as diyne cross-metathesis, ring-closing diyne metathesis, and diyne depolymerization- macrocyclization. Structure-activity relationships are to be developed by variation of the ligand sphere and determined by theoretical methods, e.g. hybrid QM/MM approaches. To develop and support the mechanistic understanding of catalytic diyne metathesis and competing diyne disproportionation, central intermediates such as propargylidyne complexes and alkynyl-substituted metallacyclobutadienes are to be isolated and structurally characterized.