Intrinsic property of multiple bonds between transition elements and main-group elements is a kind of harmony of these two elements. Metathesis reactions of carbon-carbon multiple bonds catalyzed by carbene and carbyne complexes is a representative example of such harmony.
We have previously succeeded in preparing a germylene complex 1a and silylene complexes 1b-c, and we recently discovered the methods for converting these complexes to germylyne and silylyne complexes 2a-c. Synthesis of silylyne complex 2c was achieved starting from silylene complex 1c by stepwise abstraction of a proton and a hydride. This silylyne complex 2c was isolated as an eight-membered cyclic dimer 3, and 3 was found to be in equilibrium with the monomer 2c in solution. Silylyne complex 2c underwent [2 + 2] cycloaddition with the C=N and C=O bonds of organic compounds at room temperature.
A Silylyne Tungsten Complex Having an Eind Group on Silicon: Its Dimer−Monomer Equilibrium and Cycloaddition Reactions with Carbodiimide and Diaryl Ketones
T. Yoshimoto, H. Hashimoto, N. Hayakawa, T. Matsuo, H. Tobita,
Organometallics 2016, 35, 3444-3447.