Carbenkomplexe aus koordinierten 2-siloxyphenylisocyaniden
摘要:
2-Trimethylsiloxyphenylisocyanide (2) reacts with W(CO)5(THF) to give the complex [W(CO)5(2-Me3SiO-C6H4-NC)]. Upon hydrolysis of the Si-O bond with KF/MeOH the heterocarbene complex (benzoxazolin-2-ylidene)tungsten(pentacarbonyl) (5) is formed via intramolecular nucleophilic attack of the phenolic oxygen atom at the isocyanide carbon atom. (Benzoxazole)tungsten(pentacarbonyl) (6) is formed as a side product in this reaction. The heterocarbene complex 5 can be deprotonated and alkylated at the ring nitrogen giving (N-methylbenzoxazolin-2-ylidene)tungsten(pentacarbonyl) (7). Complexes 5, 6 and 7 were characterized by X-ray diffraction studies.