Fourteen-electron bis(dialkylsilylene)palladium and twelve-electron bis(dialkylsilyl)palladium complexes.

Stable transition-metal complexes with divalent silicon ligands (silylene complexes) have been extensively studied because of their important role in many catalytic processes. Since the pioneering works by Zybill et al. and Tilley et al. , various base-stabilized and base-free silylene complexes have been synthesized and their versatile reactivity has been well explored. Although complexes with two or more silylene ligands are expected to show interesting bonding properties and reactivities that are not observed in monosilylene complexes, such complexes are still limited to donorbridged bis(silylene) complexes and complexes having cyclic diaminosilylenes as ligands. During the course of our study on the application of dialkylsilylene 1, which is the

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