Transition Metal Silylenoid-Catalyzed Atom Transfer Reactions

4 Transition Metal Silylenoid-Catalyzed Atom Transfer Reactions 

Tetrasubstituted silanes are also sources of silylene. Suginome and coworkers reported that palladium catalyzed the transfer of dimethylsilylene, formed from silylborane 44, to alkynes [equation (7.8)], 60 Exposure of silylborane 48 and alkyne 49 to substoichiometric amounts of palladium and P(7-Bu)2(2-biphenyl) afforded 2,4-disubstituted silole 50. This process tolerates a variety of functionality including silyl ether-, dimethylamino-, and trifluoromethyl groups. In addition to aliphatic terminal acetylenes, arylacetylenes were also competent substrates. For 

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